It depends on the kind of crossing. If it's a pedestrian crossing that crosses one street, then the button will do something, the first time. If it's a road junction where the lights control traffic going in different directions, and also has a step in the sequence for pedestrians, then the sequence will run in the same order every time regardless, and the button is just there so you feel like you're doing something.I am making a joke but I didn't know many actually do nothing. I thought they do something if you push once but nothing after.