Why study for exams? Are they not about what you know, not about how much you can cram into your head the night before?

There is an issue with learning anything that, if you do not use that knowledge, i.e. have a need to recall it, recall of it become unreliable. In work situations, for example, wise employers don’t send their employees on a training course for some new technology months before the employee will start using the new technology - they wait until the employee is about to start using the new technology so use will consolidate the learning.

Revision before an exam is to bring back to mind the things you learned, then parked before moving on to the next bit of the syllabus, so it is all fresh in your mind when you sit the exam. It’s an artificial situation that doesn’t reflect how useful you would be in a non-academic environment and, if everyone else will be doing their revision, why handicap yourself by not doing it?

Revision is, of course, no substitute for studying properly when each part of the syllabus is first presented. That’s the time to make sure you understand it and ask questions if you don’t.