Teaching isn't always easy and while it can be emotionally rewarding, it certainly isn't financially so -and sometimes, it's not even emotionally rewarding. Over on Reddit, ex-teachers recently discussed what it was that made them stop teaching and the answers are equal parts revealing and depressing.
One of the worst examples:
I was in one of the worst schools in the nation... one day a little 6 year old girl told me that she and her sisters were being sold to men every night for as long as they could remember. I think something broke inside me that day. When I went to the principal to discuss a course of action (calling police, DFACS, etc.) she said she wanted me to keep my mouth shut. She was tired of her school "looking bad".
Edit: because so many people are asking, I immediately called the police and DFACS. The principal was later arrested on drug charges. But I had already quit at that point.
Another heartbreaking story:
I had a 6-year old pull a knife on me while screaming "I will kill you". This was the culmination of a lot of various incidents with the same kid. What was most infuriating was the parents claiming they had the sweetest little boy and that we (the school) must be liars for saying otherwise. Eventually he was transferred to a special school after we filed a report on the various incidents.
You can read all the rest of the stories here.