Because it changes your alignment, and all your stroke components and their relationship to each other.
Imagine a Terminator type armature, and then just move any one component -- say the forearm of the grip arm -- and then try and get the armature into shooting position. If you moved the forearm up, or down, or sideways, all the other components now have to move to accommodate that change. Maybe the wrist has to rotate a bit, the legs must change their footwork, the head ends up a little lower or higher or to one side. There would be more, but that's just for starters.
You end up in a final shooting position but it's when you put the whole Rube Goldberg contraption into motion that you're going to see different results.
I would argue that that is why, every blue moon, we all fall into dead stroke. You've got all the pieces set up just so. But, day-to-day, we being less that perfect, change something -- maybe just one tiny thing -- and that in turn changes everything else and dead stroke goes poof.
Lou Figueroa
Sorry I still don't understand the analogy?
If you do the chicken dance BEFORE you get down on the shot and then ONCE YOU ARE DOWN you are ROCK SOLID and dead on the the aiming line what does it matter whether you did 3 backflips prior to that point?
In fact I know a player who specializes in the theatrics BEFORE he gets down to shoot.
When he steps to the table he plants his foot on the aiming line. If he wants to make the shot he puts his foot dead on the right line, if he wants to miss it he puts his foot down slightly off. Then he stands there and "agonizes", and whines, and pump strokes, and gets up and gets down, and back up, turns around, makes a joke, waves his cue, etc, etc.....he has a whole repertoire. When he finally get down on the shot though he is ROCK SOLID and DEAD ON LINE.
He taught me this technique as part of his hustling 101 lessons.
So I respectfully disagree Lou. I don't subscribe to the idea that every little thing you do PRIOR to getting in the shooting position affects the stroke - WITH THE EXCEPTION of doing things which make you contorted and unable to stroke properly and using CTE certainly and unequivocally does not do this to the player.
Your use of terms like "Rube Goldberg contraption" to unfairly characterize CTE is misleading. The actual process is simple and fast.
It's literally 1,2,3 and you're down on the shot in the shooting position on the proper aiming line.
Some people "get it" right away and others need personal attention. Same thing with Ghost Ball and any other concept in pool.