I’m going to assume that you are asking about the supposed desire of females to have a penis. (involved with oedipus complex for girls, Sigmund Freud).
If you mean just our culture revering large penises…then I don’t know what’s up with that? A sign of fertility or masculinity I guess? There have been many cultures that don’t worship great big penises.
Edit: I forgot to say that this theory along with other Freudian theories have come under a LOT of fire.