I think its because Quora is a tight-knit community that is not (well) aimed at a wide public audience. Increasing status can lead to tangible benefits. If you

I think its because Quora is a tight-knit community that is not (well) aimed at a wide public audience. Increasing status can lead to tangible benefits. If you are popular within the community, its essentially networking which can lead to investment, job and other valuable opportunities. SO on the other hand, is more oriented at helping people coming in through search engines. (I would like to say it has better answers because its a more hacker oriented community that reflects open-source communities, but that would probably be an over-generalization. probably...)