Dont know how to fix it

You’re comparing apples and oranges.

You have to choose a photo from the same moment in time. The photos you selected are generally from earlier on in the motion when the palm does face down.

Here are a few photos from basically the same moment in time (e.g. close to foot plant). Notice that the forearm is closer to vertical…

Why precisely is this bad?

Because that would put the forearm in a position of pronation at that point, which means the pitcher would then have to supinate their forearm to get their palm facing the target. Supinating at that moment focuses the load on the UCL and may be one of the things that makes pitchers need Tommy John surgery.

Even those pics that you posted prove my point. The palm isnt facing third base in any of those and they are later in the arm path than cav’s is. My point has been made, at the point where his hand is in the arm path, his hand should still be facing down. There are no ifs, ands or buts about it. It is physically incorrect to have the ball facing any position but down/back until the arm is pronated, during an overhand motion. If the ball faces anyother way, you either 1) dont throw over the top or 2) have a major delay in your arm path. Try to throw a ball by turning it over at the bottom of your arm path. You will not have any velocity and you will place a ton of strain on your shoulder. The pics that I posted, no matter what point they are in during the arm path, prove that the ball/palm should be facing down or behind until the fore arm is rotated to throw the ball to the plate.

Also, you are looking at the first picture in the list of three, aren’t you? That is what I am talking about. I am not sure if we have been talking about the same photo.

I’m not disagreeing with you about the position of the hand but I do want to ask you about what you mean with this statement. Are you speaking of the arm slot being “over the top”? If so, why is this a good, or necessary, thing?

No they don’t, because the palm isn’t facing the ground.

In the case of the Greg Maddux photo, that is pretty much the same moment.

I put in the photo of Freddy Garcia to demonstrate how much things vary from person to person.

Sorry, but you’re wrong.

I have taught myself to turn my forearm over early (so that my PAS palm faces 3B sooner), and I throw from a high arm slot, with plenty of velocity, and with no shoulder problems.

Arm slot has nothing to do with which way the palm is facing. Arm slot is all about how much the shoulders are tilted.

Where exactly are you getting your information?