Pitching machines have done many good things for baseball. They help little league players learn to stance and timing without being afraid of the ball. They familiarize batters with different pitching styles in a controlled environment. And they allow for repetitive batting practice without wearing out a pitcher's arm.

Do pitching machines ruin bats?

With dimple rubber balls used for pitching machines, this effect only worsens. Even bat manufacturers agree on this matter. Unless you have money to burn, there's no valid reason for using a new or expensive bat in the cage.

Do MLB teams use pitching machines?

Machines can throw real pitches, in randomized sequences and randomized locations, much like actual baseball pitchers. Obviously, it's not as if the pitching machine was just invented. Every team uses them. But that's where the real practice gets done.