"Social media is itself as temporary as any social gathering, nightclub or party. It's the people that matter, not the venue. So when the trend leaders of one social niche decide the place everyone is socializing has lost its luster or, more important, its exclusivity, they move on to the next one, taking their followers with them. In the real world this is called Bar-Hopping, in the online world the one they move on to is called Social Hobo. Now you know how you got here.