What's driving a lot of the idiotic investment is FOMO (fear of missing out). It is a powerful thing and can override a rational assessment of a businesses chances for success.

This combined with a lack of historical perspective is dangerous. Nearly _every_ smartphone app you see had a voice/phone counterpart a few years ago (remember 777-FILM or #TAXI?), most of them are long dead, and were killed off by the same market forces that will release their latest mimics from their mortal coil.