Actually it is the excuse I used to eliminate teaching as a career choice very early on. I was good at math. I majored in math early on.
I also suck at explaining math at people who don't intuitively grasp the concepts the way I did. I would be a terrible elementary school teacher, and *maybe* a decent (but not inspiring) math teacher in high school.
IMO the best person to teach a subject to the masses is the one who has struggled long enough to know which parts are hard, have had to explore different paths to understand it... and finally mastered it.
And +1 Austin, obviously. Teaching something you love/like (and not something you fear) is also key.
