MySpace completely failed to stay with the times post-acquisition, they kept focusing on catering to big-name bands rather than the huge base of individuals. Over time people grew tired of MySpace being indifferent to them and moved on. Today the same type of crowd has made Snapchat a huge success.
AOL remained fixated on catering to their existing customer base and trying to grow high-margin dial-up revenues. They squandered their capital even harder than Yahoo did, as there's not a single AOL branded anything that's a best-of-breed. Everything about the company is second rate. Consider this: They bought the internet's darling company, Netscape, and could not make a nickel off of it or even keep the brand alive in any useful sense despite investing heavily in a series of increasingly bizarre reboots.
Facebook, by comparison, will not hesitate to incorporate features from other competing products if they think they're going to drive the platform forward and has made a number of strategic purchases like Instagram and Oculus to help cement their relevance.
I'm not even a fan of Facebook, but I admire their tenacity and their incredible ability to survive in an industry littered with the wreckage of previously huge social empires.
