GMAT Self-Study Prep Mistakes

UPDATED FOR THE NEW GMAT IN 2024

In our decades as GMAT tutors, we’ve seen both the benefits and the pitfalls of self-study.

We meet piles of students who make tremendous progress when they study on their own, and at most, they need only a little bit of GMAT tutoring to help them harvest a few extra points.

On the other hand, we also meet students who develop absolutely terrible test-taking habits when they self-study – and those students ultimately waste tons of time and money undoing those bad habits via tutoring.

Obviously, the biggest benefit to self-study is the delightfully low price tag, but when students prepare for the GMAT Focus Edition on their own, they often make study mistakes that lead to bad test-taking habits or inefficient use of GMAT study materials.

So if you’re considering the self-study route, you may want to consider the following pointers (and warnings) on how to avoid the biggest GMAT prep mistakes.

GMAT Self-Study Mistake #1: Bad Verbal Habits

Based on our experience with thousands of students over the years, we’ve noticed that most students don’t struggle with the GMAT verbal section for the reasons that they expect. The main weakness holding down many test-takers’ verbal scores isn’t their fundamental reading or logic skills. Rather, it’s bad test-taking habits, which are often the consequence of avoidable GMAT self-study mistakes.

To be clear: reading skill matters. Actually, it matters a lot, on both verbal and Data Insights. Check out this video for more on the importance of basic reading ability and other GMAT-relevant verbal skills, or read this article for advice on how to improve your overall reading prowess.

But here’s the thing: since you’ve probably been reading for at least a decade or two, a couple months of studying for the GMAT won’t have much effect on your fundamental reading level. What you might be able to change in a couple months, however, is your test-taking approach. So when it comes to preparing for the GMAT verbal section, the bulk of your score gains will likely come from developing a reliable process that you can apply on every single question.

That’s where GMAT self-study mistake #1 comes in.

Let’s say that you’re incredibly motivated to improve your GMAT verbal score, so you immediately start churning through official GMAT questions. Unfortunately, if you’re just applying the same, bad test-taking habits on every set – such as skimming Reading Comprehension passages too hastily or letting outside information influence your analysis of Critical Reasoning questions – you’re unlikely to improve.

In fact, if you’re repeatedly applying the same, flawed process on every question, you’ll end up ingraining those bad habits more deeply – and you’ll make them even harder to fix later.

In our experience, many capable and highly motivated students accidentally head down this unfortunate road. When those students eventually hire a GMAT tutor for guidance, they end up spending too much time, money, and energy just unlearning their bad habits.

So what can you do to avoid this GMAT prep mistake?

If you plan to stick with self-study, you may want to read our verbal beginner’s guides to help you understand what good test-taking habits look like on GMAT Reading Comprehension and Critical Reasoning, respectively. This comprehensive collection of GMAT verbal videos might help, too.

When you study on your own, you’ll generally want to emphasize the quality of your practice, not just the quantity. When you assess your performance on GMAT homework sets, you’ll want to invest time in determining where your test-taking skills broke down, then make a deliberate effort to change them on the next set of practice questions.

Ultimately, honing good test-taking habits will probably require both quality and quantity. But be careful not to ramp up the quantity of your homework for its own sake. Keep in mind that every time you practice good test-taking habits, they become stronger. But every time you practice bad habits, they become harder to fix.

GMAT Self-Study Mistake #2: Inefficient Use of Official Verbal Questions

GMAT study mistake #2 is mostly just another unfortunate consequence of mistake #1. Basically, if you burn through a ton of official GMAT questions without improving your test-taking habits, you could end up running low on high-quality practice questions too early in the process. Then, if you try to fix those bad habits later on, you might not have enough questions left.

Because the creators of the GMAT invest literally thousands of dollars in each official GMAT question, we’re adamant about sticking to official questions for verbal prep. For that reason, you should think of official GMAT verbal questions – and the six official mba.com practice tests for the GMAT Focus Edition – as an incredibly valuable, non-renewable resource.

If you need a supplement for Critical Reasoning and Reading Comprehension, official LSAT® tests provide a nearly unlimited supply of great practice with similar, high-quality questions.

The takeaway: whenever you tackle official GMAT verbal questions, make sure you’re focusing on improving your test-taking habits, and not just doing reps for the sake of reps.

If you’re self-studying, you’ll want to be even more careful with the six official mba.com practice tests. This video will help you make the most of those official GMAT practice tests:

GMAT Self-Study Mistake #3: Making Careless Errors on Quant & Data insights

As with verbal, we’ve noticed a potentially counterintuitive trend with our GMAT students on both the Quantitative Reasoning and Data Insights (DI) sections. For many test-takers, the main issue holding down their quant and DI scores isn’t poor reasoning skills or a lack of content knowledge. Instead, the biggest problem is – wait for it – bad test-taking habits, yet again.

On an adaptive test like the GMAT, you’ll get yourself into all sorts of trouble if you make careless mistakes on questions that you’re capable of answering correctly. The test’s algorithm attempts to determine the level of question at which you get roughly 50-60% of the questions correct – so your GMAT score is ultimately determined more by which questions you miss than by how many you miss.

The bottom line is that sloppy errors can cause your GMAT quant or Data Insights score to spiral downwards in a big hurry. Nevertheless, we meet tons of students who frantically – and sloppily – practice quant and DI questions, in an effort to build their content knowledge and problem-solving skills.

But then many of those same students ignore the fact that their process is erratic, and they make score-killing careless errors as a result.

We’re not saying that content and reasoning skills don’t matter on GMAT quant – far from it. But partly because of the proliferation of free GMAT video content like this quant series and this DI course, many test-takers can learn GMAT content fairly easily and cheaply. Unfortunately, learning all of that quant and DI content doesn’t necessarily prevent students from developing absolutely terrible test-taking habits during their self-study.

This article and this video include a rundown of what good test-taking habits look like on quant. In a nutshell, these habits include being extremely methodical and systematic to avoid careless errors, along with skipping questions that you’re likely to miss anyway.

As with verbal, many capable and motivated GMAT quant and Data Insights students accidentally make the mistake of reinforcing their bad test-taking habits while self-studying. The better option is to treat each set of practice questions as an opportunity to both evaluate and hone your test-taking process, with the goal of eliminating unforced errors.

If you’re struggling with careless errors, your score is unlikely to improve consistently unless you’re laser-focused on developing a systematic approach to quant and DI questions. Even worse, each time you practice a bad habit on a GMAT quant or DI set, the habit becomes harder to fix.

GMAT Self-Study Mistake #4: Inefficient Use of Official Quant Questions & DI questions

All of the same points about official GMAT verbal questions also apply to official quant and Data Insights questions. While non-official quant questions can be useful in a GMAT prep plan, there’s no substitute for the official stuff. No matter how hard a test prep company tries, they’ll never fully capture the complexity or subtlety of official GMAT questions – and on some of the more nuanced Data Insights question types, non-official questions might not come anywhere close to resembling the real thing.

So again, you’ll want to be as strategic as possible when using official quant questions, and stay focused on developing good habits. Otherwise, you could find yourself with a shelf of burned-out official GMAT books, and a dozen bad habits you’re still hoping to fix – or not even acknowledging at all.

This is particularly true for Data Insights questions. Because the Data Insights section is relatively new, there are fewer official questions available for DI than for other GMAT sections. So please use them carefully.

Okay, So Given the Drawbacks, Should You Self-Study for the GMAT?

The honest answer: at first, you won’t know. You may go in with the best of intentions, be hyper-conscious about avoiding key GMAT self-study mistakes… and still end up spinning your wheels and burning through official GMAT questions without making enough progress.

That said, after you’ve done a few weeks of self-study, there are a couple of useful litmus tests that can help inform the decision about whether to keep studying on your own.

First, is your performance improving? You’ll have to track your data to answer this question, so create a spreadsheet when you start studying and update it each time you do a set of questions. We find that LSAT® RC and CR questions are particularly useful for this purpose, since the difficulty does not vary significantly from set to set.

If you’re making steady, incremental progress, great: that’s a sign that your self-study plan is working, and you’re presumably not making major GMAT prep mistakes. If you’re not making progress at all – or if your performance is wildly variable from day to day – that’s a problem, and it might be time to consider a prep course or a GMAT tutor.

Second, do your mistakes provide actionable takeaways? This question is far more complicated than it seems at first glance. If, for instance, you miss a Critical Reasoning question because you didn’t pick up on a subtle quirk of language on an answer choice, it’s not enough to just read an explanation online, and think, “oh cool, now I understand what that answer choice meant!”

Instead, you’ll need to ask why you missed that subtle quirk of language – and whether you habitually make similar mistakes. If you identify a recurring weakness in your skills, you’ll then need to consider how to adjust your behavior to minimize the probability that you’ll repeat the same mistake on the GMAT. For example, did you freak out about time, start reading faster, and skip over some important modifying words? Did you fall in love with a different answer choice, and not give the correct one a fair chance? Or were you making some other mistake?

This last piece – correctly diagnosing yourself – is by far the trickiest part of self-study. If you can do it effectively, that’s awesome.

But if you struggle to identify the underlying causes of your struggles, you’re not alone. We all have blind spots, and sometimes it’s useful to have a GMAT tutor, a study partner, or a test-prep course instructor help you figure out which mistakes you’ve made in your GMAT studies.