[Hrm, how to explain this...]

It's a part of the game. You score by running all the way around the base, see? But the guys on the other team are trying to get you out - uh, out of the game, that is. They do that by tagging you with the ball. So the farther away they hit the ball-

[She punctuates this by miming a batter swinging at an illusory baseball]

-the longer it takes for them to catch it, and the longer it takes for them to catch you.