It's the ultimate fortune teller of a hitter's future production. Everyone loves to search exit velocities to see whether a hitter has a projectable future, but it's one level deeper where you find the context behind a hitter's performance.
Since it entered the public tracking space in 2023, bat speed has arguably been the most important metric, correlating with almost every major league performance stat. SLG%, OPS, wRC+, ISO, Barrel%, Hard-Hit%, BABIP, you name it: bat speed correlates strongly with all of them. Simply put, the harder you swing the bat, the likelier you are to produce at the plate.
Best of all, it only needs a small sample to become meaningful. With just five competitive swings, you can start drawing conclusions from bat speed. That helps a lot when you're trying to tell whether a hitter's swing change is working, whether he's playing through an underlying injury, or whether …