It's an OLD and boring mechanic that need to go away in 2.0..

It is the only thing that make some fights "kinda" difficult, only because the hate control in this game is the worst ever.

Every game has taunt that put you 1° in aggro. And everyone should stop dps till the tank make some threat.. Here not. And this at 99% of cases make useless to use Raise on a tank after he die for example.