Smart girls? Are you out there?

Most men aren't looking for a secure, smart woman, too intimidating for them. Even the ones that say they do don't like to be challenged and still hold certain traditional notions about what is appropriate female behavior. Gender norms are ingrained early on and constantly re-enforced. Females are socialized to be nice and fit in with the group, it's a whole different value system than what males are brought up with. For the women that are secure, there's no need to make a fuss or try to get attention, so they simply aren't as noticeable.