Why should we clean our ears after having shower?

You should not. Your ears are intended to be self cleaning. You should shake the water out of your ears or use a commercial drying agent to prevent fungi from growing, but that is all you should need to do.
Should not. You should not need to clean your ears after shower.Some pts put q tips too deep into ears without realize till i see them and tell them that their ear drum is red. If you feel some water in ears after showers then use q tips gently to clear off water, but outside only.