It Runs Faster and It Runs Further!
Girls always want the strongest, or the fastest, or the most spiritual. Guys always want the smartest, the most beautiful, or the best kisser. We always want the -est.
We look for someone that is the best in one way or another to be with. They are valued greater by those around them than the lesser achievers. By gaining the attention of said person we feel like something has been achieved in ourselves to make us that much better.
Yet this doesn't simply apply to dating relationships, those that appear great in the social eye have done something to raise themselves up on a pedestal, they where the -est at something.