Teachers or instructors that took the time to go over the material and speak about it. The ones that talked about irrelevant subjects and then assigned reading, basing their tests on the reading were hard for me. Due to ADHD and problems with my eyes, I could not read well. Tell me something and I'll not forget, at least until test time, even insignificant details.
AFA tough vs. not so tough, it didn't make any difference to me. I was going to learn it through listening or not. One thing I had a beef with was the various grading systems. Each teacher set their own grading rules. The strict curve was bad news for me in some instances. If there was a lot of cheating in that class, my grades sunk. And I called them on that. So some teachers and I had a difficult relationship. If they walked out of the classroom during testing, I was apt to follow them.
All the way to the principal's office.
I read better now at old age. Go figure.