Do you remember Google Plus? Google had excellent financing and an existing team of excellent software developers and couldn't pull of a credible alternative to facebook.
The world is littered with the expensive corpses of failed software.
Much of Facebook could be cloned by many startups see VK.
Google's product lacked purpose. It died because of a lack of vision and leadership and product mistakes (real names).
It died prematurely. Google treated the product like a pilot a network threw on the first week of September. It had solid numbers and given time it could have found itself if it found a backer in leadership.
The world is littered with the expensive corpses of failed software.