I always thought, that people with best way of teaching certain things have to struggle with that subjects themselves. A mathematician isn't going to teach me shit, because for them, the relations and the way to solve problems just comes naturally, they deduce it. I don't. But someone who isn't good at maths or physics, had to find an explainable way, tried and managed to understand it, and can teach me that way. Instead of saying things like "naturally", ''apparent'', "logically" or "then you easily deduce" .