Immediately after you conclude the GMAT and before the computer displays your scores, you are given the option of canceling your scores. Canceling your scores is almost always a bad idea.
When Not to Cancel
1. People routinely overestimate or underestimate their performance on standardized tests
The GMAT isn't a test on Science or General Knowledge, so knowing how well you did isn't always easy. As long as you answer most of the questions and are able to focus reasonably well during the test, you will probably earn scores that aren't too different from the average scores you'd get if you took the test repeatedly.
People who retake the GMAT and other standardized tests rarely see their scores change significantly unless they are initially unprepared to take the exam and later attempt it with significant preparation.
2. You may not have time to reschedule
It may take a while to reschedule the test. If your applications are due right away, you could miss an application deadline because you don't have GMAT scores to submit.
3. You will never know how you did
If you cancel your scores, you will never know how you did or what areas you need to work on to improve your score if you decide to retake the test later.
When to Cancel
A few circumstances exist in which you should consider canceling your scores. These situations aren't based on your estimation of how you did, which may be inaccurate, but on extenuating factors:
1. You are not well during the test
Waking up on test day with a high fever or getting sick during the test may warrant canceling a GMAT score.
2. You were unable to concentrate during the test
Unusual personal difficulties, like a death in the family or the demise of a close relationship, could distract you to the point where you freeze up in the middle of the exam.
3. You left many questions unanswered
If you forget the time management techniques and you leave quite a few questions unanswered in the verbal and quantitative sections, you may consider canceling your scores.