Brilliant screenwriter and techie John August puts it best:

Every once in a while, your character chimes in, but it’s generally to say, “I’ll do it!”

The decisions have been made and you’re sent off to do/get/kill whatever they’ve decided upon.

I finished Diablo 3 many weeks ago, and I have barely felt the urge to pick it back up since. In fact, it was difficult to finish because I felt so completely uninvested in the actual quest. Despite what some may believe, level grinding and stat-rolling does not constitute a quest.