ESO is a reskinned WoW with no raiding. What will you do once you hit max level? Most people jump around and chat then quickly get bored of doing that and stop signing in. Most P2P MMOs are just trying to copy WoW's formula, but seem to be highly lacking in endgame content. Then they wonder why they have to go F2P. FFXIV ARR is apparently having this very problem right now.
F2P games just aren't making it these days in terms of longterm players. Sure they work, but they don't bring in the type of funds necessary to continue development of endgame content. Most play the game, have a ton of fun for a couple months then quit once they hit max level with maybe 1-2 raids. Then come back for the small incremental updates and leave again.
Raids and difficult encounters require much more teamwork between players, strengthening that social aspect of MMOs. Without it, its almost like playing a coop campaign game. Once you beat it, you usually don't go through it again. If players stop playing a P2P game, they cut developers, which means less new content, which means more players leaving. I see ESO going F2P a year after launch.
