Pre-move Time Deduction??

I would like to know why I keep losing on time when I've made a pre-move that is legal following my opponent's move. Isn't the idea of a pre-move to not let your clock run??????

In live chess or regular? In live chess, their are still bug issues, and the lag compensation couple with bad connections and an imperfect platform are just something you'll have to deal with. But if it's regular OTB you're talking about, either your opponent made a move off the predicted line and your premove didn't work, (because the line changed) or your opponent moved twice - once before and after the premove.

Live chess. By the way, your comment about my pre-move not working because the position changed fails to recognize that I said a pre-move that is legal following my opponent's move.

So this is a lag issue, huh? Thanks.