A lot of the problems these companies cover are interesting to everyone. Search is interesting to everyone, maintaining a social network is interesting to every

A lot of the problems these companies cover are interesting to everyone. Search is interesting to everyone, maintaining a social network is interesting to everyone, buying stuff online is interesting to everyone. Cab-sharing is not interesting to everyone. Staying in strangers' homes instead of a hotel isn't interesting to everyone. Taking photos of your meals and sharing it with friends is not interesting to everyone.