All good hitters get jammed

The title seems very misleading. How can you get jammed and be a good hitter? Well, ultimatley you can't. You need to make consistent contact on the barrel of the bat. The statement is in comparison to the opposite of getting jammed- hitting the ball on the end of the bat.

Good hitters seldom pull off the ball so early where they hit the ball on the end of the bat.

It's quite simple. To be a good hitter you must be able to handle any pitch the pitcher throws. Now, this is a very difficut proposition. But, the best hitters do not handle 1/4, 1/3 or even 1/2 the plate. They can handle the whole plate. In order to do this, they must first be able to handle the outside corner and then adjust to the inside corner. To attempt the opposite makes hitters very vulnerable.

So, if a hitter is looking away and can't quite adjust to the ball in the hitter would be jammed.

At amateur levels of baseball it's a very easy thing to recognize when observing young players. If they are getting jammed rather than hitting the ball off the end of the bat, their flaws are at the least the best of two evils. Something to consider.