My university offers a teaching certificate - possibly to make you look good on the job market, possibly so you feel that all that effort you put into your teaching was worthwhile - which requires two videotape consultations. A lead TA, trained in the consultation process, comes to your class and videotapes you; then, within 24 hours, you watch a small chunk of the videotape and come up with a teaching "issue" that you can work on. Seeing yourself displayed on the TV, in the unflattering amateur camerawork, is a universally horrifying experience. Choosing to have the tape recorded to DVD for posterity is optional.
After my first videotaping, I didn't even considering getting the DVD. Why in the world would I want a record of that? It was my first semester teaching (my third as a TA, but the first two had involved nothing more intense than answering emails and proctoring exams), I had no idea what I was doing, and at the time half of my life was dedicated to finishing my master's thesis. The consultation was very constructive, but the class itself had not been pretty.
My second videotaping came almost two years later, with two more semesters' experience in teaching that particular lab. The consultation was still constructive - there's always something to work on - but I was more horrified by the sound of my voice (I hate the way it sounds recorded) than by my teaching. And if I succeed in my career plans, and become a full-time teaching professor, then someday I might want a record of what I was like "at the beginning". Not the absolute beginning - I will never regret not getting that first DVD - but with a minimum of experience and the carefree life of a graduate student.
Not that I have any intention of watching the DVD now. It'll be bad enough reading the student FCQs without throwing my own harsh opinion into the mix.