My university had a Programming Fundamentals course in the first semester and we got assigned this grumpy lady who demanded respect and would always claim she was the best at programming among her colleagues, had an obnoxiously snobbish tone and had a habit of forcing unneeded nonsensical sarcasm everytime one of us stepped up to ask her a question.

She taught C++ and I'm not saying she didn't know her stuff or anything; I respected her regardless (because she was my teacher), but she would mix up C classes in and insist that that was the right way to do it and had no consistent programming style.

Once she got so fed up with our class that just to prove her point that we're all dumb and worthless (she hated us a lot, yeah) that she started explaining binary trees and recursion out of the blue and gave us assignments for them... even though they weren't going to be covered that week. It soon became a shitfest, to be honest.

But on the plus side, because I didn't wanna listen to her lectures I pulled two all-nighters and covered the semester's worth of C++ and started napping in a corner in her class. She never had personal beef with me so I was thankful for that but her being the way she was helped me learn C++ with more motivation and vigor than I normally would have and also let me earn some change because my classmates couldn't understand her classes and wanted me to explain whatever she covered.