Or maybe the class was full of slow students. I once had a math professor explain he stopped grading on a curve because he once had a class where the highest g

Or maybe the class was full of slow students. I once had a math professor explain he stopped grading on a curve because he once had a class where the highest grade was a low C and he didn't feel that deserved an A. And I agree with him. You're there to learn, the grade isn't supposed to be a reflection of your effort. I once had a class where the professor would put things on the test that weren't in the lecture. Caught me off guard the first time, didn't catch me off guard the rest of the semester. The gap between my grade and everyone else in the class was huge (I think I'm the only one that passed in that class). --- At the end of the day, if a student cannot show some sort of mastery of the subject, they should be failed.