Why Study?

Yesterday morning, on the radio, I heard an advert for a rock festival saying "Relax between the end of classes and your exams - come to our festival, you deserve it". I was amazed. I can only conclude that either:

1. The course teaching has instilled the basic principles and techniques so well that studying for the exam is unnecessary.
2. Given that all that is required is to know the answers to a restricted number of questions which always come up in the exam, cramming the night before the exam is sufficient.
3. It's acceptable to risk failing one or two exams, because they can always be re-taken in September.

Maybe I'm missing something here, or I have forgotten how it was when I was a student.