Who decides if people have to wear a mask or not?

Is conscience of humanity being divided in the ones wearing a mask and telling others should wear one too and the ones not wearing a mask and telling others they dont have to?

Governments come up with rules and regulations on how citizens should or should not behave. if you have watched broadcasting for a bit and looked around you. no one is following up on the rules, not even the rulers who implement them.

The Corona crisis is an obvious display that people can not be contained nor behavior forced upon.