User blog comment:Jenburton/Coming Soon: Message Wall in Labs/@comment-1788742-20111024213044/@comment-1207433-20111024230708

The more features you make optional, the more potential configurations you can have. The more potential configurations you can have, the harder it is to make sure that they all work together properly.

If you have 6 optional features, that's 65 ways you can configure a single wiki. That means every time Wikia makes a change to something in the UI, they have to make sure it doesn't break in any of those 65 possible configurations.