PPC management mistakes can come in all shorts of shapes and sizes. Some are small, and don’t end up costing you very much in the end. Others are large, and if not addressed quickly and properly can really break the bank.
In the PPC world, one where you have to “pay to play,” you can’t afford to let these mistakes pile up. Each mistake runs the possibility of costing you ad spend, conversions, and the trust of your audience.
Whether you’re an in-house Marketing Manager, a PPC Manager at an agency, or a C-level Executive looking at your current agency situation, understanding which mistakes are passable and which are disastrous is important.
This post will cover the PPC management mistakes that we see most frequently. And, more importantly, what you or your PPC agency should be doing to fix them.
I’ll put it bluntly. If your agency isn’t at least working to solve any of the problems below, it may be time for you to consider other options.
This postcolor> will cover 22 different PPC management mistakes we often see, plus how they should be fixed. The list of mistakes is organized into 6 different categories:
- Mistakes Before Setup
- Account Setup Mistakes
- Keyword Mistakes
- Ad Creation & Testing Mistakes
- Account Maintenance Mistakes
- Bonus: CRO Mistakes
That’s no small list of possible issues, so let’s get rolling.
Mistakes Before Setup
It turns out that there’s plenty of mistakes an agency can make during the onboarding process itself. Before they even get their hands on your account there are a few things you should be looking for when you are signing on with your PPC agency.
The below three mistakes could be considered “red flags” for a new agency that might not be focused in the right direction. And by “right direction,” I mean generating more sales and growth for your business, while increasing ROI.
Mistake #1) Failing To Align With YOUR Goals
One of the simplest but most frustrating mistakes we run into while managing PPC accounts is a failure to align success of the account with success of the company itself.
It’s nice to grow clicks and traffic via your paid campaigns. But if you aren’t converting leads and generating actual sales/revenue for your client, all you’re really doing is costing them money.
And no CMO or CEO wants to spend $3000/month on agency retainers if they aren’t actually generating sales.
More often than not these issues arise because the agency prioritizes tracking vanity metrics instead of legitimate KPIs. So, what’s the difference between vanity metrics and KPIs? You can check out the image below to help clear that up.
Vanity metrics can not only deceive you into thinking that an account is performing fine, they can also lead you down some dangerous rabbit holes that can burn serious budget.
For example, if you’re prioritizing how much traffic your ads are generating (and shooting to maximize this vanity metric) then you might end up chasing massively broad keywords that aren’t relevant to your actual offer.
According to your traffic volume metric, your goal is being hit. But, in reality, all you’re doing is paying for more and more traffic that isn’t relevant to your actual offer and thus isn’t actually converting.
You’re paying more and more without making any new sales. And…..cue despair:
Another big mistake that even the best PPC agencies end up making is failing to align their metrics and KPIs to the specific business goals of their clients. Or settling for generating sales instead of generating growth, in the more specific case.
It may be the case that you signed on with your agency with no experience in the paid advertising space. And thus, everything they’ve done is an add-on to your existing marketing efforts.
But, it’s often the case that companies who hire a PPC agency already have their own PPC campaigns running. When this is the case, some agencies settle for setting optimization-based goals that simply fix the problems in your account.
But that isn’t where optimization is meant to stop.
As an agency, your clients don’t want you to simply serve as another advertising channel. They want you to grow their company.
I’m talking about generating better returns from each of their campaigns — not just shooting to improve conversions, but improve ROI, LTV, and the real needle pushing KPIs.
Mistake #2) Targeting The Wrong Metrics
The second mistake we see agencies make can be another way to get sucked into tracking the wrong metrics. That problem is failing to set up goals and specific tracking for those goals.
Failing to set up goals for your account is a big PPC no-no. Not only that, it’s a big red flag that shows that whoever is managing the account is grading their success based on CPC or CTR. While these metrics are important, if they are your measure of success you’ll find yourself chasing more clicks and traffic without considering the quality or intent of those clicks. You’re bounce rate will most likely sky rocket, and your conversion rates will plummet.
Mistake #3) Skipping Google Analytics Integration
Setting up goals in Google Analytics and connecting your account to your Google Ads account is the first way to remedy this situation. Which is why forgetting to integrate your Google Ads and Google Analytics accounts is such a simple, yet costly mistake.
One that you shouldn’t forgive any agency for making, of course.
Luckily, it’s an incredibly easy fix to setup your goals in Google Analytics (GA). Just click the Admin tab in the bottom left of the GA interface (the gear icon). You can see in the screenshot below that the Goals tab is on the right column.
Just click the Goals tab and it will take you to the view of your campaign and all its goals. You can either click the red + New Goal button or you can choose to Import from Gallery to create a new goal.
When it comes to creating goals you basically have 3 different options:
- Create a custom goal
- Use a goal template
- Create a Smart Goal
Now this post isn’t about creating goals, you can read all about that here. But suffice it to say that setting them up is vital to your success. What type of goals you set up is dependent on what type of campaigns you choose to run.
However, these goals should prioritize user actions that lead to actual needle-moving, revenue-generating improvements for your brand. Conversions like lead form submissions, online sales, and email signups are some of the most popular — but they aren’t the only ones.
Each campaigncolor> has a specific ROI generating conversion that you or your agency should be tracking like a hawk.
Why? Because that’s the metric that you’re going to take to your boss when you ask for a raise 😉.
Account Setup Mistakes
Some of the most costly PPC mistakes are made during the initial setup of the account. You could consider this a snowball effect of sorts when it comes to cascading negative effects.
Trying to cram too many keywords into any ad group, or too many ad groups into any one campaign can make tracking and optimization a nightmare. And setting things up like a knotted ball of yarn will leave you wasting a lot of time untying that knot later on.
Likewise, simply leaving a few boxes checked or unchecked when you first launch your campaigns can leave all too much power in Google’s hands when it comes to how your budget is spent.
These mistakes may seem small. But it’s very important you stay sharp and make sure you double and triple check before you click “publish” to make sure your campaigns start off on the right foot.
Mistake #4) Segmenting Your Account Wrong
Let’s start out with a KlientBoost favorite.
We’re firm believers that, when it comes to account setup, there’s a north star that PPC managers should always follow: The SKAGs technique.
Even though Google may suggest that you bundle keywords by theme into a single ad group, this is actually a dangerous way to segment your campaign.
Why? Because doing so can seriously damage your search-to-ad message match.
Segmenting your account with multi-keyword ad groups based on theme may seem like it makes things easier for you. But search engine users aren’t typing themes into the search bar. They’re typing actual search terms.
You want these search queries to align as closely to your keywords as possible. Ideally, 1:1.
This is why Single Keyword Ad Groups (SKAGs) are such a win. They segment your ad groups and ads based on singular keywords so you can use the different match types to target only single search terms as well.
And it doesn’t stop there. Setting up your account with SKAGs also gives you a nice granular view into each of your ad group’s performance. Even if sometimes it can mean scrolling through quite a few ad groups.
Mistake #5) Being Too Loose With Geo-Targeting
This is a fairly simple mistake. And, not to sound like I’m anti-global-integration. But the fact is that there’s plenty of countries where you have no business targeting. So make sure you take a comb through your geo-targeting and eliminate any illogical locations.
Heck, our own geo-targeting is pretty much restricted to the U.S. and Canada.
It may seem like a simple mistake, and yet on the other hand — if you offer the right digitally communicable service — it would even sometimes make sense to target your ads globally. But as is the case with most things in the PPC industry, less is more.
You’ll be surprised how much ad spend you can save by narrowing your geo-targeting down to where you know it’s working best.
Mistake #6) Letting Google Handle Your Bidding
When you first click into your Google Ads account you’ll notice that Google already has some default settings chosen for you.
The default settings can include:
- Ad Frequency (don’t blow through you weekly budget in half a day)
- Location Targeting (“people in your targeted location,” not “people in or interested in your targeted location”)
- Automated Bidding Strategy (stick to Manual as opposed to Automated – keep control)
- Enhanced CPC (Stick to Manual CPC, with Enhanced CPC Google will optimize your ads’ performance for clicks as opposed to conversions)
You can go ahead and chuck these out the window.
Now, this isn’t to say that trusting Google to help you with your PPC performance is always a mistake. But it’s important to remember that Google gets paid for every time anyone clicks on your ad, regardless of whether that click leads to a conversion, sale, or bounce.
This meanscolor> that Google’s goals aren’t quite aligned with your own in terms of generating legitimate growth, revenue, and ROI out of your campaigns. Google is far more interested in generating as many clicks for your ads as quickly as possible.
And, just like chasing the wrong vanity metrics, letting Google take the wheel can lead you down some dangerous paths.
Don’t let Google lead you up blind alleys and down dead ends — take the reins for yourself. It’s your money, you should decide how it’s best spent.
Now that you’ve had the time to go through your account structure to make sure everything’s A-Okay, it’s time to checkout how you’ve organized your keywords. Or, how your agency has organized your keywords.
These keywords represent the the trenches where you’ll be fighting most of your PPC battles. So making sure they’re properly setup and mistake-free is well worth the investment and energy.
*Hint Hint* The below mistakes will each touch on a different keyword-related PPC issue that the SKAGs technique solves. I told you we’re big believers didn’t I?
Mistake #7) Not Bidding On Your Brand Name
Let’s make one thing simply and painfully clear. If you aren’t bidding on your brand name, your competitors are.
Or at least they are if they know what they’re doing.
Your brand name keyword serves as a unique opportunity for your PPC keyword strategies. In terms of intent, this keyword represents the highest level purchase intent of potential traffic clicking on your ads. So you want to make sure that you’re showing up when someone is explicitly searching for you.
Now, to better understand the important of bidding on your branded keywords, let’s take a look at a typical branded SERP (search engine results page).
Even though you’re more than likely to rank #1 organically for your brand name keywords, that doesn’t mean you should step off the pedal. As all digital marketers know, above-the-fold content tends to generate more views and engagement. And it turns out that about 65% of those views are spent in the top half above-fold-content.
And what lies at the top of the SERP, within that 65%? You guessed it — that’s where the ads are.
This means that if you’re relying solely on your number 1 organic ranking, you’re the fifth viewable link on a SERP that should be all about your business.
Leaving your brand name keywords open to PPC poaching allows competitors to place competitive ads based on price differences or superior offers that target your potential clients. Protect your herd, and keep those conversions to yourself.
Mistake #8) The Iceberg Effect (Broad Match)
The Iceberg Effect is one of the biggest and most costly PPC management mistakes plaguing digital marketers. In its simplest terms, the root mistake that leads marketers towards the Iceberg Effect is confusing keywords with search terms.
Keywords are what you bid on within the Google Ads platform to trigger your ads to show. But search terms are the actual words and/or phrases that users are typing into the search bar.
Bidding on keywords that carry a heavy iceberg with them is a costly mistake, one that the SKAGs technique works to fix. These heavy-iceberg-keywords are costly to your PPC performance because they have a high keyword:search term ratio. That is, they have many search terms triggering the same keyword with the same ad within your account.
This means that your ads need to fight to stay relevant to a much larger audience of varying search intents than you can possibly account for.
And so, you end paying for a bunch of clicks that don’t find your actual landing page relevant to their search, and thus bounce off.
You’re paying without converting again — the cardinal sin of PPC mistakes.
Mistake #9) The Mob Effect (eCommerce)
The Mob Effect can essentially be boiled down to the eCommerce equivalent of the Iceberg Effect. Basically, the mob effect is a problem that arises when your budget is poorly allocated towards poor-selling products with high search volume, as opposed to high-selling products with low search volume.
I know, I know. When it comes to PPC, we’ve been conditioned over and over to try to optimize our campaigns for the most clicks and traffic possible. It’s why we target high search volume keywords in the first place.
But, even if it may go against your stronger PPC instincts, the truth is that when it comes to traffic, less is often more. Or — to be more precise — you want quality traffic over quantity.
The Mob Effect is a product/keyword-driven problem that can cost you a serious amount of cash. Especially in the eCommerce game when your conversions are directly attributable as sales, your revenue calculations should be fairly straight forward. And you do NOT want them to look like this:
You should be maximizing your budget on your most high-selling and highly-profitable products. By re-allocating your budget towards winning products and segmenting your traffic towards these isolated campaigns you can eliminate budget burn while maximizing ROI at the same time.
Mistake #10) Having A Weak Negative Keyword List
The last PPC management mistake related to keywords concerns your negative keyword list.
Regardless of whether it’s at the account, campaign, or ad group level, your negative keyword list will best help you avoid wasteful spending on irrelevant keywords.
By continuing to update your negative keyword lists (at all levels of your account) you’re able to guarantee that your ads don’t trigger for any keywords that you don’t want to pay for.
Now, the reasons behind adding a keyword to your negative keyword list can be many fold. For example:
- Overlap with another SKAG you’ve already built
- Keyword deemed relevant by Google but not by you
- High search volume with low to zero conversion intent
- The list goes on…
Negative keywordscolor> are vital to ensuring that your SKAGs don’t overlap and you don’t waste ad spend on pointless variations of the same keywords. Especially if you’re using the SKAGs technique and employing multiple match types for the same root keyword, this is worth avoiding.
This is why neglecting your negative keyword lists is such a big PPC management mistake. Without the barriers of control around which keywords trigger your ads, you’re liable to burn quite a bit of budget.
Ad Creation & Testing Mistakes
Ad creation and testing is where you finally get to start showing your creative side in the PPC game. However, this is also where you can run into quite a few PPC management mistakes if you don’t stay focused on the right goals and the right reasons behind your testing variations.
Blind optimization, when digital marketers randomly decide to change campaigns or ads based on “hunches” or “gut feelings” as opposed to data, is a prime example of burning budget with the best intentions.
Avoiding the below four mistakes will help you avoid blind optimization and keep your ad creation/testing focused on what matters.
Mistake #11) Being Boring With Your Ad Copy
Being boring with your ad copy is the simplest mistake you can make in terms of ad creation. Even if you’re using the SKAGs technique correctly, and are placing your keyword in the headline and path of your ad (maximizing relevancy in Google’s eyes), that doesn’t mean you’re good to go.
It’s always absolutely vital that you remember that — no matter what means you’re marketing through — your end audience is a human being, not Google.
So throw some flavor in there and make sure your ads are still enticing enough to get users to click.
Always remember that it’s a human on the other end of the search engine that you’re trying to reach. Don’t let the technical mumbo-jumbo drag you down into an automated sense of PPC marketing. You’d be surprised what a little personality and flavor can do for your brand:
Mistake #12) Forgetting To Account For Message Match
Another big ad creation mistake actually concerns the landing pages these ads link to.
This is where message match comes in.
What’s message match? Well, think of it as the relevancy of your actual landing page and it’s offer to the ad that your user clicked on originally. You don’t want to lead users from an ad they think is answering their question or providing them the service they need, to some landing page that is totally bogus.
It’s essentially getting catfished by a PPC ad.
Ignoring the landing page when your first creating a new ad, or editing the offer of an existing ad, can be a costly error. This is where your actual conversions are going to take place, so you want to ensure it’s a smooth customer experience.
When a user clicks on one of your ads you’re making an implicit promise to help solve their problem/pain point:
The promise that you make, which causes them to click needs to then be reflected into your landing page copy — the headline and subhead — if you want them to know that they’ve made a good choice and have come to the right place.
– Johnathan Dane, KlientBoost CEO
Neglecting to do so can really devastate your not only your conversion rate, but your audience’s trust in your ads moving forward as well. Which is never a good thing.
Mistake #13) Not Accounting For PPC Traffic Temperature
Like message match, it’s important you also account for the temperature of your incoming PPC traffic. Just because you have the right product/service for your relevant clicks, doesn’t mean you have the right specific offer.
Too often these days, digital marketers report their conversion rates as a lead marketing pain point. This makes sense if you consider that we all want more leads. But once you take a look at the actual landing pages, the “problem” becomes more of a mistake on their part.
And what’s that mistake? They’re asking for way too much off the bat.
Just because a user clicked on your ad for, let’s say, a new home security system, doesn’t mean they are ready for you to show up with your installation team and get going. There’s a progression of different level offers that you need to consider, each with their own “temperature”:
- Read Article (ice cube)
- Learn More About Offer (cold)
- Download eBook (warm)
- Get Quote/Estimate Now (hot)
- Buy Now (lava)
This is what we call the Ice Cubes and Lava approach. It can take some testing to identify what the general temperature of any given ad’s traffic is. But once you identify it, it’s important you consistently match the temperature of your offer to the temperature of your incoming traffic.
Otherwise you’ll never see any sustainable growth or improvement for your PPC campaigns.
Mistake #14) Changing Too Many Things At One Time
When it comes to PPC testing pitfalls, one that nearly all marketers fall into is testing too many variables at one time. Especially if a landing page is drastically underperforming, it can be very tempting to throw the whole variant out the window. Or, at the very least, dramatically change nearly everything about it.
The problem with this is that, even if you do see a significant bump in conversions, you have no idea what specific change lead to what percentage of that increase.
You’re left blind to which optimizations caused which improvements. And this can make future optimizing an equally blind struggle.
Isolating your tests and split-testing or multivariate testing a single aspect of your page at a time is the best way to accumulate accurate data on which optimizations work best.
It may take a bit longer, but the results will always be worth the time.
Mistake #15) Not Giving Tests Enough Time To Run
The last testing mistake that PPC managers can make is not giving their tests enough time to run. “Growth hackers” and other sketchy digital marketers like to believe that weekly sprint tests are possible. But in most cases, you simply don’t have enough traffic and data to consider these results statistically significant.
And without that, you can’t really feel confident making decisions based on these flimsy test results.
Think of it this way — you want to try out a new coffee restaurant but it only has two reviews, one 5 star and one 1 star. That type of data doesn’t exactly inspire confidence, now does it?
Account Maintenance Mistakes
You may think that if you’ve address your account setup, your keywords, and your ad creation, that your PPC optimization is complete.
Well, sorry to burst your bubble, but you’d be wrong.
Maintaining your account and continually optimizing it is as important as keeping fuel in your car and changing its oil. You can’t simply drive off the lot and assume you’ll be good to go until you buy your next car (start your next campaign).
The below PPC management mistakes can show you just how costly ignoring your campaigns after launching them can be.
Mistake #16) Failure To Worship The Search Terms Report
Any PPC marketer who is truly working to continually optimize and grow his/her campaigns worships the Search Terms Report. This is one of the greatest gold mines of new keywords that you have access to.
Your search terms report (to be distinguished from keywords) will show you what actual users have typed into Google to trigger your ads to show.
This is a great resource for identifying new keyword opportunities to build new SKAGs around. It’s also helpful for identifying new Icebergs growing around your existing keywords that you can break up with negative keyword lists.
As a whole, however, the true power of the search terms report is the ability it gives you to stay up to date with your ads. Search engine behaviors is an ever-growing amalgamation of trends and user intent. So setting up your campaigns and thinking they’ll continue to run as evergreen ad campaigns is foolhardy.
Make sure you’re maintaining your existing ads as much as your creating new ones to grow your audience. Otherwise, one day you’ll check into one of your campaigns to find some terrifying corrosion.
Mistake #17) Not Adding To Your Negative Keyword List(s)
This may have been mentioned as PPC mistake #10 already. However starting off with a strong negative keyword list is different than maintaining and adding to your existing list(s).
In order to make sure that your different SKAGs and campaigns don’t overlap with one another, negative keywords are a must.
Otherwise, you open yourself up to keyword cannibalization which can cost you serious money in the long run.
Mistake #18) Not Re-Allocating Budget To Winning Ads
Lastly, before we dive into the bonus mistakes regarding CRO, I want to talk about moving around your PPC budget.
With all the different PPC automation and helpful scripts available to PPC marketers these days, it’s real easy to get complacent once you hit a nice stride with your PPC performance.
As long as you’re bringing in new traffic, keeping your bounce rates down, and continuing to creep up that conversion rate, you may find yourself hitting “autopilot.” However just hitting the bare minimum goals isn’t enough to truly drive successful growth for your clients.
And any agency worth its salt is going to try to drive legitimate growth, not just dollars, for their clients. Because of this, regardless of which technique or strategy your employing, you ought to be moving the money from your paused campaigns towards winning opportunities.
So if you’recolor> debating on where to fit your remaining ad spend, and you’re caught between two ads (A and B), and B is outperforming B, you shouldn’t just pause A and keep running B.
Take the budget that was previously allocated to A and start increasing your bids, run time, budget, etc for ad B. This way you have more backing behind the better running and you can start to grow your most successful channels.
Bonus: CRO Mistakes (Because PPC & CRO Are Intertwined)
It’s a sad truth, but many a PPC manager has no idea what CRO entails. Even though the two are inextricably connected, many a PPC manager will simply optimize your keywords and bids as best they can before they hand off your account to a designer or back to your own in-office team, dusting their hands like they’ve completed a job well done.
It’s pretty straightforward logic that, if you’re paying for clicks that send users from your ads to your landing page, you should take the time to make sure your users enjoy the page they land on.
Because of this, we at KlientBoost believe that PPC and CRO are categorically connected and vitally intertwined. A PPC optimization campaign isn’t complete without optimizing the landing page for the most conversions possible. So let’s take a look at the CRO mistakes that are haunting most PPC marketers.
Mistake #19) Ignoring Landing Page Optimization
While PPC management mistakes may occur a great deal within the actual Google Ads interface, your landing pages are where your actual users/potential leads will spend the bulk of their time. So ignoring landing page optimization isn’t really a viable option.
As I mentioned above: CRO and PPC are crucially intertwined with one another. Optimizing your PPC account for more clicks and more quality traffic is a great start. But if all of your users are clicking through those highly-relevant ads and landing on some bogusly broad landing page that doesn’t cater to their interests…well all you’re doing is spiking your bounce rate and losing money.
“It’s not about the destination, it’s about the journey.” Well, sorry to say it, but it’s a little of both in the PPC world. So start optimizing those landing pages if you don’t want to scare away your audience.
Mistake #20) Increasing Traffic Before Improving Conversions
Mistake #20 is actually a bit of a tricky one, I have to admit. But consider this: Most optimization routines are forward-facing. As in: you fix your keywords and bid strategy, optimize your landing pages and conversions, then dive into your sales process to see where it can be improved and where you can generate more revenue.
But, I continually find myself asking….Why?
In this hypothetical scenario, only the below results are possible:
- You increase traffic via your paid ads, lowering your CPC, but in the end increasing ad spend by the total clicks you generate
- Your pages generate more traffic and thus a higher bounce rate before you optimize them
- You then optimize your landing pages to increase you conversion rate, however you’ve already wasted X-days or weeks in doing so (that’s money down the drain)
- Now you have to look at your sales staff to see if they can close all the new leads your generating, and if not…
- You finally look into your sales staff optimization, after losing a solid percentage of the new leads that your PPC and CRO efforts generated.
See why I tend to take issue with the above yet? Let me paint a better picture. Try flipping the optimization process on its head. How? Well, with the bottom-up optimization routine below:
- You first look at your sales process and optimize it to the max (you’re now functioning at the highest close rate possible – regardless of volume)
- You then optimize your landing pages with CRO to generate more conversions and leads for your sales team (you essentially increase the volume given to your optimized sales staff to now close more deals)
- Finally, you optimize your Google Ads account and PPC performance to increase quality traffic, thus widening the flow of potential conversions to your optimized landing page which will lead to an already optimized sales team.
In this scenario, instead of bleeding budget at each step of the optimization process as you work out new kinks, you work ahead of yourself. You first improve the rates at which each aspect of your campaign performs, then increase the volume.
Fix the funnel before you fill it full of traffic, not the other way around. Instead of just focusing on new wins, start looking at your existing opportunities that can already be improved.
Mistake #21) Taking Any One Tactic As “Set In Stone”
Depending on what type of campaigns you’re running and what issues you’ve set out to solve within your own accounts, you may find yourself stumbling across certain solutions that generate amazing results.
However, it’s important that any digital marketer doesn’t get too attached to any tactic as a fool-proof goldmine. There are cases where we’ve seen the Breadcrumb technique not to work, and have had to adapt based on test results.
Thankfully, this is an incredibly easy mistake to fix. Simply remember that the performance of the account isn’t based on the glory of your tactics, but the successful growth of your client’s business.
Follow where the money takes you, and you shouldn’t be far off.
Mistake #22) Failure To Keep Up With Innovation (Reading)
The last mistake I’ll address in this post is not so much a mistake. It’s more just…well, a little shirksome to be honest.
The daily routines of any busy PPC manager keep them plenty occupied with their accounts. And rightfully so. But that sadly doesn’t excuse them from keeping up with the innovations of their own industry. A truly motivated and innovative digital marketer will be read up on the latests developments, updates, and trending tactics in the PPC world.
I don’t think that excuse is going to fly with anybody.
“For Want Of A Nail…”
Here’s an old proverb for you:
For want of a nail, a horseshoe was lost. For want of a horseshoe, the horse was lost. For want of a horse, the rider was lost. For want of the rider, a message was not delivered. For want of a message, a battle was lost. For want of a battle, the war was lost. All from the loss of a horseshoe nail.
The old saying is pretty straightforward — the little mistakes can add up to costly losses if you don’t catch them quickly. The good thing is that PPC management mistakes don’t have to cost you an arm and a leg out of your advertising budget if you can catch them quickly enough (or better yet, setup your account in a way that they never arise).