If it were that simple, there would be multiple Pinterests. 

But it's not that simple. There is only one.

yeah, sometimes these "Roadmap" infographics terribly diminish the struggle.  I mean, there are other pinning sites, but yes I'll bet some just gave up once Pinterest hit its rise.  Also, others focused on different intents and purposes (clipboard, keeeb, minus, et al).  Nothing is more powerful than an army of soccer moms...