TERA goes f2p cuz they're losing customers
Main reason is the game lack of end-game content, max lvl ppl got nothing to do beside looping boring dungeons, abusing the low lvl in the pvp battleground, go crazy on world chat. i know cuz that's what i did over past couple months and i saw many ppl left becuz of that, it's getting bored at the end. In general, you don't have a goal you want to achieve in the game.

Other mmos are competitors to FFXIV:ARR, but so does FFXIV:ARR itself would be a strong competitor to other upcoming mmos, i dun really worry much about it.