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In most elevators, at least in any built or installed since the early nineties, the door-close button doesn’t work. It is there mainly to make you think it works. (It does work if, say, a fireman needs to take control. But you need a key, and a fire, to do that.) Once you know this, it can be illuminating to watch people compulsively press the door-close button. That the door eventually closes reinforces their belief in the button’s power. It’s a little like prayer.

Tips from an expert (on some elevators): If you press either the floor you are on or the floor you are going to, the doors will close. If you press the door close button and the floor you’re going to at the same time, the elevator goes express.