To answer your last question: Why do you believe that?
Though teachers are often underappreciated, they have a rewarding career. Having an impact on the development of young minds and watching them mature into capable adults is something you have the power to achieve. This job can be exhausting and frustrating at the same time. However, nothing beats spending the day with adorably adorable kids.
A child’s personality can be sweet and innocent, but it can also be unpleasant or even cruel sometimes. People who act this way usually have no malice in their words and blurt out whatever comes to mind. Students are expected to learn this, but it is an ongoing process for teachers. There’s no way a teacher wants to be in that position.