Yeah, you.
What is the reason you and will continue to, PvP in FFXIV? I'm just curious as to what gives other people their own incentives to do so.

Me? Well aside from me maining PvP in just about every other MMO/Game, to put it short:
The unpredictability and excitement I get from playing against other (real) people far beats any dungeon, boss, loot, story, quest, in PvE.