To add on to what Grogmar said, take one of his Skyrim quips: "M'aiq has heard the people in Skyrim are better-looking than the ones in Cyrodiil. He has no opinion on the matter. All people are beautiful to him." I probably shouldn't have to explain that.
Then compare it to an Oblivion quote: "M'aiq prefers to adventure alone. Others just get in the way. And they talk, talk, talk." To the best of my knowledge, this is explaining why Bethesda didn't put multiplayer in Oblivion.
Kind of a useless post since Grogmar summed it all up. It's just reinforcing the idea, but, meh. Got nothing else to do today.