It actually did better than SFIV in Japan when you consider how many PS4s there are compared to PS3s. It sold several times the amount that SFIV did per console.

@Johnnycide The most played game in the world was released in the same kind of way, though, albeit without an upfront charge. League of Legends has had dozens and dozens of characters added - all of which cost either real money or in-game currency earned by playing - as well as the core gameplay changed by years of frequent patches.

Another insanely popular game is Hearthstone, and that also has new cards released every few months that cost either real money or in-game currency. Entire modes were added to the game years after its release. Another of the most successful games of all times, World of Warcraft, is on its 6th expansion and has had new races, regions and classes added - as well as massive changes made to every element of the game. Take any year that WoW has existed and its had totally different features than the previous year.

All of those games (plus many more) have been released like piecemeal and have real money/in-game money purchases throughout, and are some of the most successful games of all time. I don't actually think that's the problem, I think it's the genre itself. It died before and was brought back by SFIV. It's since faded away again and it looks like this is a case of lightning not striking twice. Of course, it's also a problem that the PS4 isn't doing as well as the PS3 in Japan.