Why do ladies have to hit the smaller ball?
The idea behind the smaller ball for ladies is to allow them to hit it farther and therefore increase their chances of getting a hit as well as even the playing field for Co-Ed (where the umpire switches the ball for male/female batters). These balls are not only smaller (11 inches in diameter as opposed to 12) but they are often harder (core 47 or 50 vs. core 44) and therefore they do fly farther when hit.