Biggest problem for MMOs right now is that there are too many of them, all competing for the same players. They also face competition from various other sorts of multiplayer online games (MOBAs, First Person Shooters, etc., etc.)
This makes it hard for any of them to get enough players to be profitable, and player communities will also often be a bit too small to be really self-sustaining.
This leads to the games and playing experience not being as good as it could have been, with the result that when something new comes around a bunch of players will jump at the newest shiniest thing hoping that this time things will be better. It won't be better, and now the older games have even fewer players.
This makes it hard for any of them to get enough players to be profitable, and player communities will also often be a bit too small to be really self-sustaining.
This leads to the games and playing experience not being as good as it could have been, with the result that when something new comes around a bunch of players will jump at the newest shiniest thing hoping that this time things will be better. It won't be better, and now the older games have even fewer players.
