When I miss high its usually because my arm is not getting around fast enough, so as a result, I release the ball too far back, or too high, or too soon, or whatever it would be called lol and my pitch winds up high. For me personally, it usually happens when I get tired because my arm slows down and my body’s still moving at the same speed so my arm gets up a split second too late and my release point becomes a little too high.
Remember release point is everything, if the ball’s high than you’re releasing the ball too high.
I can’t seem to find an adjustment to make for myself yet simply because it only happens when I’m tired so I don’t want to go and change something about my mechanics because they work fine when I’m not tired, instead I just have to get in better shape, I think lol.
One suggestion that this coach I had once made that made a lot of sense was to start my arm a split split split second sooner than I was that way it has that split second longer to get up and throw from the right release point. Make sense? I suppose you could also try speeding your arm up? :? I guess…
But, being that it only happens 1 out of 10 pitches, I’d say to just work on repeating the right release point. Make sure you release the ball at the same place every pitch. Maybe 1 out of 10 pitches you’re overthrowing, or 1 out of 10 you’re getting lazy with your arm on that pitch maybe.
I’m not an expert so hopefully that makes some sense and can help a little bit. Good luck.