I answer Stack Overflow out of mainly self interest. I don't have a portfolio of work to show people at job interviews - my work is mainly in house. I realized

I answer Stack Overflow out of mainly self interest. I don't have a portfolio of work to show people at job interviews - my work is mainly in house. I realized it isn't that hard to get a decent score on SO if you know something well. Also because it annoys me seeing things done poorly having worked in enough maintenance programming jobs and worked with crap that could have been done so much better (this is probably a bigger motivation with certain topics). I don't do it because I feel I owe anyone anything. It does feel good to contribute somewhat, but that is far from my primary motivation.