remspot

I am wondering why you have to have the suspension at normal height when tightening your ball joints or sway bar endlinks. Aren't they just a ball in a pocket? So if you tighten them with the suspension loose or on jack stands won't they turn and swivel into position when placing the car back down? I understand the logic of the other bolts and bushings but a pivoting ball and socket seems ok to tighten when up or down.