agreeing with rab, a symetrical face is a physical sign of having 'good genes' for want of a better phrase. we are programmed find symetry attractive and as rab says a mole decreases this. smooth skin too is a sign of youth which we subconsciously associate with fertility. of course we are all now far too sophisticated to let a little biological programming affect whether we are attracted to someone aren't we........................not :-)
nobody's face or body is symmetrical however, take a close look. - and moles, beauty is in the eye of the beholder and as these critters live mostly underground - maybe because they're ugly :-)