WHY?

Why do we have to press the button to cross the road at traffic lights?

Is it too difficult to assume that at some point of the traffic-light cycle a pedestrian might want to cross the street?

There are two sets of traffic lights in Sydney that work correctly as far as I know, in that they assume there are pedestrians therefore do not require a crossing button. They are in Crows Nest, at the intersections of Hume & Oxley Streets with the Pacific Highway.

I don’t know why more sets of lights aren’t like this – surely it would be cheaper not to build all those buttons.