Agreed. All traffic light buttons do something in Dublin, as far as I can tell. Most lights are at junctions. If you don't press the button there, there will be

Agreed. All traffic light buttons do something in Dublin, as far as I can tell. Most lights are at junctions. If you don't press the button there, there will be no point in the cycle where you're guaranteed no cars will cross your path. If you do, there will. Some traffic lights are just for pedestrians crossing, away from a junction. Normally those work pretty quickly - traffic stops in 10 seconds, so long as the last stop was at least 30 seconds ago. In some countries, pedestrians can get a green light while cars are still allowed turn across them. I'm not sure if that's the case in New York, but it might explain some of the confusion.