I'm a teacher, and I've had quite a few bad ones. Mind you, this was in the 80s-90s, in a typical Midwestern town!
My third grade teacher would physically intimidate the children. He used to throw books, smash chalk, and tip over students' desks. Poor kids would cower and cry. I used to have daily panic attacks about school, due to this man.
My fourth grade teacher sat all of us "leftys" in the back row, and tried to convert us to write right-handed.
My sixth grade teacher used to scream at the class to gain control, and would cry on a regular basis.
My high school band director would throw temper tantrums, have paranoid delusions that students were mocking him, and gave erratic grades, based on his mood. We were not allowed to ever look at a clock or watch. That would enrage him, that we were perhaps eager to leave. He would send students on personal errands - to buy gifts for his family, pick up dry cleaning, to get him something to eat, etc. I used to take weekly bassoon lessons with him, which terrified me. He once asked me why I never would blink my eyes. I think I was scared stiff.
I had high school English and history teachers that would just have us copy the textbook and turn pages upon pages in, to prove what we "learned."
I had another history teacher that would sit the pretty girls in the front row. He would ogle them.
My debate coach used to insist on driving me to and from debate matches. One time, when we were alone in his car, he cried and told me he was lonely.
My 12th grade English teacher was resentful that he had to teach "us," a group of non-"Honors" students. We weren't worthy of having names. Instead, he assigned us numbers. I was #19. If you didn't turn in your paper in order (in my case, between #18 and #20), he would give you zero credit. He called this treatment "real life," and told us to get used to it -- menial labor, and not worthy of being called by name. He expected all of us to be failures in life. He threw me out of class once for sneezing too much. Finally, when he learned of which colleges I was accepted to, he told me I was lying. I ended up attending the same university as his daughter, perhaps out of spite.
My first year teaching, I had replaced a teacher who was resentful about a forced retirement. He was asked to retire, after he took a group of students "camping" on his own, and let a lot of wild things go on. He took a job as a building substitute, and would undermine me, by taking students out of my class to hang out with him, and sending students to spy on me, and suggest to them that I was teaching them incorrectly. I took over his after-school club, and he would regularly join us. Once, he convinced a group of students to trespass with him in a closed-off park, and then had an illegal bonfire with them. I was there, trying to control the group, and they all went along with him. I was so afraid of losing my job, because of this man. If I was ever absent, he would switch subbing assignments, so he could come to my class. He would go through my personal things, and change grades in my grading book. He would lecture the students that they shouldn't listen to me, and he was their "Papa." Finally, I called for a meeting with him and our building principal. In the meeting, he lost his marbles and screamed at me that he hated me. In an equally unprofessional act, the principal fired him in front of me.
While I was in graduate school, I had a horrible professor that would try to use the Socratic method, but would just fire off students' names, and when they were unable to quickly answer, she would tell the student they were going to fail. On the first day of class, she told us that half of us were going to drop/fail by midterm, and she would take the time to learn our names after that time. She was right - half of the class did leave. She was so nasty to me. I had been a high school teacher for six or seven years at that point, which she never bothered to know, but she told me in a heated meeting, "You will never be a teacher. You will never make it." I fired back at her that I was already a teacher, and this made her hate me more. I have colleagues that have had this professor since then, and they have said that she wasn't too nasty. I don't know why she had such a horrible attitude with me and this class. She hated every single one of us, and went out of her way to try and trick us with material. She would test us on material she never gave, would write tests that were humanly impossible to finish in the time allowed, and would ask the most obscure, irrelevant questions, just to try and trick us.
& hopefully not like one of your horrible teachers!