It's surprising that I've been so interested in self-portraits over the last year, given that most photographers, including myself, will do anything to avoid being in front of the camera.
I've done a bit of reading and apparently artists make self-portraits for a variety of reasons, including: self-promotion, emotional purging, the convenience of a free and willing model, or the opportunity to experiment with new techniques.
I think I fall into the last category — where I feel compelled to make others look attractive, I don't mind distorting my own image ... I'm happy to mask my identifying features with psuedo pixels and tattoos in order to take meaning to new levels.
I'm sure a psychologist would have fun with that!