Example match I experienced: I popped into a game in progress. My team was on Alderaan and barely losing. We were 390 to 410. We could have easily turned the match around, but at least six people refused to move from the taken turret.
There needs to be something to keep more than two people from protecting an objective that isn't under attack. It's not hard to call "left", "right", "mid", whatever when you have incoming,