Expert: The 5 Worst GMAT Study Mistakes

There’s no secret recipe to success on the GMAT exam. If you want to raise your score by more than a few points, you’ll have to do it the old-fashioned way, with hours of quality studying. 

Unfortunately, the “quality” element is often elusive. We’ve tutored thousands of GMAT students over the years, and the same study mistakes pop up again and again. 

So here they are: the 5 worst mistakes to avoid during your GMAT prep.  

1. Self-Sabotage: Ignoring Unforced GMAT Errors

When you make a careless mistake, you might just write it off as a fluke. You “knew” how to get the right answer, so you can move on to other questions, right? 

Nope. If you ignore your unforced errors and don’t address the sloppy habits that caused them, you’re likely to make similar mistakes on test day. The adaptive GMAT algorithm doesn’t care why you make a mistake. All it knows is that you missed an easy question, and it’s going to bludgeon your score accordingly.

So if you’re making unforced errors, it’s absolutely crucial to figure out why. If, for example, you misread the question, was it because you were rushing? Were you too overconfident to check your work? Nervous? Sleep-deprived? 

Once you have your diagnosis – whether you’re working with a tutor or on your own – you’ll want to create a concrete, specific action plan to address the underlying behavior that causes those sloppy errors.

2. Misusing GMAT Practice Exams 

You only have six official practice GMAT tests from MBA.com. That’s it. When those are gone, you can’t get more, and non-official practice tests are nowhere near as accurate as the real thing. Sure, you can retake the exams, but familiar questions can easily make practice exams feel nothing like the real thing.

So we can’t say this enough: please don’t burn through your official mba.com practice tests too quickly.

Instead, intersperse them throughout your studying to identify weaknesses. After taking a practice exam, return to other materials to work on your blind spots. Once your other practice data shows clear signs of improvement, then you’re ready to check your progress with another official practice test.

3. Obsessing Over Probability & Minor GMAT Quant Topics

Here’s a fun fact: probability accounts for about 2-3% of all GMAT quant questions – an average of less than one probability question per test. Yet we’ve seen plenty of students devote a ton of time to probability even though the probability (ahem…) of seeing a pile of these questions on test day is close to zero. 

This isn’t sexy, but the overwhelming majority of GMAT quant questions are rooted in algebra and arithmetic of one flavor or another, including word translations and percentages. If you want to study efficiently, focus the bulk of your energy on these topics – and not on probability, combinations, permutations, and other subjects that appear only occasionally.

4. Binge-Studying for the GMAT

Binging doesn’t work. Period. 

Many elements of the GMAT – including nearly everything that appears on the verbal and Data Insights sections of the exam – simply cannot be learned quickly. And the topics that can be learned quickly will be less likely to stick if you study in unsustainably long marathon sessions. 

Instead, your goal should be thoughtful, balanced studying. Start with the subjects that deserve the most time and then gradually phase in the other topics. Also, it simply isn’t effective to “cram” as you approach your test date. The final weeks of your GMAT prep should be devoted to honing your strategy and making sure that you’re rested, relaxed, and focused when it matters most. 

5. Too Much Memorization

There’s very little that you need to memorize for the GMAT exam, which is far more concerned with testing how you think than testing what you know.  

Consider Critical Reasoning, for example. You could spend hours internalizing the solutions for individual practice questions, but you won’t see those same questions on the actual exam. As soon as you see a question that’s worded slightly differently, you’re likely to be completely lost if your study strategy is dominated by memorization.

The same goes for quant and Data Insights. Both of these sections reward flexible reasoning, not rote memorization. If you go on autopilot and blindly apply a memorized formula, the smallest wrinkle in a GMAT question will derail you.  

It’s fine to memorize a handful of basic rules at the beginning of your prep. But once you’re a little further along, you’ll want to focus on maximizing the flexibility of your thinking, especially under pressure.

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Charles Bibilos has served as a GMAT and GRE tutor since 2001, and has achieved perfect scores on both exams. His company, GMAT Ninja, specializes in online GMAT and GRE tutoring and coaching to combat test anxiety.

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