I... Honestly don't think the Vita is really failing.
I mean, I own some games on it, some PSP and PS1, but mostly Vita titles and I love a majority of them Heck, the recent Soul Sacrifice can even challenge Gravity Rush in (my personal) best Vita exclusive. The other Vita games are pretty damn good, the ones I own anyways. LBP, Ragnarok Odyssey, All-Stars, Soul Sacrifice, Gravity Rush, BlazBlue: Continuum Shift Extend... Yeah, all pretty good or great games in my own opinion. I even have 3 friends who own Vitas themselves, my brother owns one, and I have a friend who only has a PS3 and I can play All-Stars with him. Cross-Play is a great thing!
As for the argument of Vita failing... When my friend said that no one owns a Vita, I popped up the article of the Vita outselling the 3DS and the Wii U to make him go "Oh." so there'd be a bit of peace between us...
I guess that's my two-cents on the matter.