Learning vs. getting good marks

I've come to the realization that getting good marks doesn't always mean that you're learning well. By learning well I mean that you're actually accumulating knowledge that you will retain, and can use, after you write an associated test and or exam.

I try to learn but I do some cramming because I am convinced that cramming before a test can improve my mark by about 5-10 percent.

I know someone who almost exclusively crams. She starts to study a few hours before a test and ends up getting really good marks. She doesn't seem to know anything, unless she's about to write a test. It's kind of odd and kind of annoying. What's even more annoying is the fact that she's aware of her problem and talks about it frequently.