I'll disagree. While every MMO may go about it differently, there are a few fundamental rules that need to be adhered to or you either bomb the launch or your customer base churn is too high.
1. A MMO is a Multiplayer game, all activities in the game must therefor be "better" in multiplayer than the single-player-in-a-multiplayer-world experience. If people only come to play the single player part and then leave, you've failed.
2. A MMO-RPG, must allow the player to create and name their own character within the programming limits of the game. In otherwords you can't have a MMORPG where everyone has to play Fluffy, and the world is populated with only other Fluffy's.
3. A MMO-RPG must have a clear path on why they are in the world. You can't just drop someone into the world, go "here's a spoon, have fun" and not give them an objective. What's the ultimate goal, reach level 50? Kill the bigbad? Craft a nice house?
Final Fantasy XIV hits most of the right notes when compared to other RPG's. I don't expect it to be perfect (everyone is going into trendy minecraft-clones now) but It just wouldn't be a Final Fantasy game if there wasn't deep lore and story behind every character. This is not a "WoW-clone" with a Final Fantasy skin on top. Most of the MMORPG's out there clone WoW's mechanics but offer very little originality, and all the freemium ones want you to spend hundreds of dollars a month on cash shop items to stay ahead. No thanks. The amount of money you might spend on FFXIV (10-15$/mo + 40$ per expansion) is equal to about 2-3 stand-alone games that give you 15-30 hours of play time each. So if you can get 90 hours of play out of FFXIV, you are FAR ahead of a single player game, and you can play with friends.
