Annie,
I wonder about the people who leave too. I think SR is like many things in life. You get out of it what you put into it. Sometimes people can get a 'quick fix' with a few responses and feel very satisfied. For me, I definitely see the rewards of staying here and getting to know people well and seeing their growth and the challenges they face. This makes me look at myself and try to be the best I can be.
Love, Anna