Cause and Effect:

Cause: Better Graphics Effect: Downgrade on Animations
Cause: Graphics Engine totally redone... Effect: Shadows Downgraded

( The above are just examples)

Get the Picture here? Sometimes in life.. you take a little give a little, If there was an MMO that did all those things flawlessly, No MMO that would come out would have a chance to beat it. You can't get one thing (Cause) and expect nothing to be potentially punished (Effect). Certain aspects of the game had to take a tiny little beating in order to push in something better on another aspect of the game.

In the end when you play the overall aspect of the game, do you really notice all the small stuff when you play the game? Hardly. Maybe at first but the more you play the more it becomes apart of you, and it becomes to not even matter anymore.