Students do not know perfectly well who the good and bad teachers are. Adults with hindsight can discern the good and bad teachers but I can think of multiple

Students do not know perfectly well who the good and bad teachers are. Adults with hindsight can discern the good and bad teachers but I can think of multiple cases where I had my good/bad flipped as a student compared to later on when I compared my knowledge level to other adults. I had a writing teacher I didn't particularly like, then I got to a good college and found out I was one of the better writers. Turns out she was pretty damn good at her job.