More like X task is impractical to do here and we believe we should have that before someone makes too good of a deal to pass up.
MMOs are making a somewhat resurgence, and more particularly they are becoming a bit more creative again- confidence that that "I'll always be the best so whatever" is probably not best placed. Maybe what caused WoW, among other reasons, to suffer as it has.
Clearly FFXIV is not on the downward spiral but given these games, honestly all games, take a long time to make it's better to be slightly ahead of the curve than WAAAAAAAAAAAAAAAY behind it. Just 'starting' after the rising sun of competition emerges is going to put you quite behind the curve.
If some company comes out with liquid gold and you haven't even started on yours yet, likely bad move. If you're just humming along in the background like many companies do with their product lines ready to strike when they feel others are about to- better. Of course still even with the somewhat resurgence of the games that they're still harder to produce and challenges to the thrones come less often. MMOs.. MOs? It's true more recently the more popular mmos have been far more personal in focus.
I doubt SE needs to have one ready to put out the door any time soon (next year or two at least I'd bet is no concern) but if they waited three years from now to start another MMO / MO (add then five or more years for development) I might imagine they could get caught with their pants down when something better shows up before they're even close to ready. (Start and or greatly enhance their current one at too much of a delay). Really cool technology out there might allow a newer mmo to do things that are just incredibly impractical with the old system.
I imagine, like FFXII (or the plan at least lol), they might be clever and help build the MMO with their sRPGs. Given (Naoki) Yoshida and Hiroshi Takai are on board with that other new FF game, and so I imagine the team knows what an MMO needs, it might be a more successful transition this time when it comes time to take that engine and 'multiplayer-ify' it. That way they cut a lot of development time down without having to invest it off into something that is too early to release while their current flagship is still capable of holding the line. Just a guess tho.