Why paint a self portrait?

This week, I painted my own portrait. All of my favorite painters have at one time or another, painted their own portrait. Why do artists do this? Many do it because models are expensive, but the artist is always present. Also, the artist can simply practice their craft without inconveniencing another person. I've also heard artists say, "If you can't capture your own likeness, how can you do it for another?" Plus painting yourself is difficult and challenges the artist in many ways. 

I used a photograph, rather than a mirror, to paint myself. I'm leaving my Dallas studio soon for Eastern Oregon. I wanted to capture my last moments in this space with a self portrait. It seems fitting. This space has made me supremely happy. Is the photo an exact likeness? Of course not. That's not really my thing. But it does capture the care-free way in which I make art and inhabit my studio.