This isn't about studying and going through it once - you have to study it, go through it with most companies you interview with, and then re-study it once you'

This isn't about studying and going through it once - you have to study it, go through it with most companies you interview with, and then re-study it once you've not done it in your job for a while. It isn't about putting in the effort. It's that even after you've provably put in the effort, they still don't believe that you've put in the effort, and so they constantly test you to make sure that you've put in the effort.