I worked in an after school program for about a year or so. I was pretty good at it and I liked it. Then we moved into a new location. I got a new boss. We did not see eye to eye.
For example, we had this one student who disrupted every class, picked fights, and would steal laptops. It was so bad that other students refused to show up because they didn't want to spend time with him. The kid was eventually expelled, but the situation was a huge headache. I left the next month, and never looked back.
But in truth, my experience was nothing compared to these teachers who quit: