Propeller or wind turbine often has only 3 blades,reason is wake behind each blade interfere with next blade.

I think wind that comes to propeller must clear this wake,so faster you go the air for each blade has better quality.

How then wake interfere with blade?

(Same like in Formula 1, there is no wake for car that drives behind car if cross wind is blowing. Or there is not turbulence at airfield when plane take off if cross wind is blowing)