So here's the long answer ...

The decision for elite athletes about which sport to take seriously comes in middle school. At that point, choices must be made about what direction to go. It's very difficult to play two summer sports, and so whatever a girl does during the summers after sixth and seventh grade is very likely what she will for the rest of her career. (And we are only talking about elite athletes here, the ones who will P4 starters and difference-makers.)

In middle school, thoughts of a career in athletics are far from a girl's mind. As anyone who has been around girls at that age knows all too well, it's all about friends. Friendships, peer groups, etc., are by far the most important factors in decisions for the vast majority of girls.

Now basketball and volleyball players are both cut from the same mold: Tall, long, explosive. (On the boys' side, this is not an issue because volleyball is not taken seriously.) So the two sports compete for the same pool of athletes.

But what's really determining what the elite athlete does is not the sport she likes best, or the coach she likes best, or what she's better at. What determines her choice, in most cases, is her friends -- and they are very likely not elite athletes, and maybe not even high school level.

So consider a middle school girl of middling athletic ability -- what sport is more attractive to her? There's basketball, with running in practice, contact, fans that scream at refs and other parents and ugly uniforms. Or there's volleyball, with no running, no contact, polite crowds (because no one really understands the game) and spandex shorts.

What sport does that girl choose? And what sport will she encourage her elite athlete friend to play?