4DSC is correct, you want to use the compound or swirl remover just shy of drying, do not buff powder or residue into the surface of the paint. Compounds were not designed for this and this will cause scratching all by itself.
As he mentioned, every situation is different. The temperature of the surface, the humidity, the ambient temperature, etc. So we can't say, "It will take two or four minutes of buffing". What you need to do is watch the viscosicity and texture of the compound. When you are buffing it, itat first is white (most cases) and relatively thick. It also gets a sort of "snake skin pattern" because of the pad and PC orbital pattern. WORK THE PC SLOWLY. Most people work too large of area as if they are pplying wax, and do it WAY too fast. You need to concentrate on a small area to break down the compound otherwise you are just spreading it around. Pretty soon you will notice that the snakeskin pattern (texture) is lessening and that the viscosity of the compound is getting thinner. It's literally getting more soupy and wet looking. It looks more shiny to the eye. At this point the outside edges where the compound is very thin will start to haze dry right after you buzz by them. This is your signal that you have broken down all the compound. I take a clean MF towel and wipe from the wet middle to the dry outside and easily clean up all residue. If needed use a QD for extra help.
Hope this helps.:wavey
