It's selective quoting:

"In evolutionary terms this sexually dimorphic trait provides no obvious survival advantages for a male, but is a likely candidate for sexual selection (Barber, 1995). Guthrie (1970) suggested its value in signalling aggression during inter-male fighting, perhaps by the perceived enhancement of the lower jaw, emphasising the teeth as weapons. This indicates that facial hair may have been sexually selected by females on the basis of associated male success, despite its threatening appearance. Clean-shaven faces therefore may suggest appeasement, as well as being an obvious sign of sexual immaturity (Guthrie, 1970). "

In short, smooth faces are gay, and women aren't put off at all by aggression, or none of us would be here.