“A successful first experience using Fix My Street is associated with a 57 percent increase in the probability of an individual submitting a second report, and the experience of bureaucratic responsiveness to the first report submitted has predictive power over all future report submissions.”
This jibes with what we observe with Front Porch Forum. People stick with it because, simply, it works. They post a request, question, call for support, etc., and they get results. So they keep participating.