I look at mine before every flight and when i am finished i look at them again. They are pretty much your lifeline. Make sure they are installed correctly too!
+1 for great advice. I check mine before every flight by running my hand up/down each edge of each blade. Also, give them a twist before flight to make sure they're still locked to the motor.
does anyone know how the silver thing in mavic air props fills the whole when put on? when i put one of my props on and lock it in, it does not fill the whole all the way has some room as if its pushed up to high