If you join your clan and one is ready to do the nightfall but he's waiting on the other guy whose in the crucible trying to get all of his bounties and the other guys are all in the middle of king's fall, you can end up wasting a good portion of your hour waiting to start the nightfall, only to bow out when you have to go do other things. I enjoy destiny, but I don't let it get in the way of my life.