Halo Effect

Facebook crushed it. It became the ultimate social network, and investors and employees made fortunes. For a while, as FB went only up and up and up, there was a Halo Effect on "anythiing social networky." That is, they all looked like the same angels for investors that Facebook did, and a ton of money was raised funding competitors. Then a ton of money was lost funding competitors. Then the Halo Effect was...no longer.