Incentives to Share
Here’s a great quote from the Plancast postmortem
Returning to the topic of sharing plans, it’s not only a matter of having interesting plans to share but being compelled to actually share them. And unfortunately, people don’t submit information to social networks because they love data set integrity or altruistically believe in giving as much as possible. They do it because the act of contribution selfishly results in something for them in return.
Most social networks feed primarily on vanity, in that they allow people to share and tailor online content that makes them look good. They can help people communicate to others that they’ve attended impressive schools, built amazing careers, attended cool parties, dated attractive people, thought deep thoughts, or reared cute kids. The top-level goal for most people is to convince others they are the individuals they want to be, whether that includes being happy, attractive, smart, fun or anything else.