The first and most obvious place a helmet visor goes is when we ride in the rain or snow. This is where it makes sense to use a helmet with a visor because if you hit a patch of ice, you won’t be able to see.
In addition, if you get a splash from a puddle or a rock on the road, you don’t want to have to worry about getting your face wet and dirty. The only time you should remove the visor is when you stop.