It's like asking why people still produce music when there are world class records out there. Or why people still write books. Teaching is a performance art a

It's like asking why people still produce music when there are world class records out there. Or why people still write books. Teaching is a performance art as well. That aside, as a graduate student I didn't have that much freedom (or didn't understand how much freedom I actually had) in making changes - and also, it was my first time as an instructor of record, so I was trying different approaches. If I teach again (currently I'm in the industry), I'll know how to direct my efforts better.