It's a round ball and a rounded bat. Now hit it square.
That's the challenge for any hitter in baseball or softball. The ball is coming in fast, perhaps dodging and darting depending on what the pitcher is trying to do, and a hitter has a split second to decide where to swing, when to swing, how fast to swing. The best hitters have great vision, quick reflexes, good upper-body strength, sound judgment and a drive to always make themselves better.
Besides all of those traits, what else do you need? The basics, of course.