Soaps are formulated for different things. Heavy duty soaps like the old brown octagon soaps loaded with lye that really clean your hands and the old lava soap with bits of pumice in it. More mild hand soaps are for when you don't need the really heavy duty cleaning and face soaps to moisturize and clean gently. Shaving soaps aren't meant to clean at all just lather well and provide cushion and lube.