Most of the time for nail holes I use the pink stuff that turns white when it is dry. Alot of the time one of the first things I will do when I get on a job is to scoop out a glob and roll it in quick dry patch powder, then kneed it into a putty. I press it in with my finger and knock off any excess that's left on the surface with the side of my hand....no flashing, no sanding. If there are larger holes to fill, I will mix some of the quick patch, patch any larger holes/imperfections, and once the mixed patch starts to dry I will kneed it some to form a putty, and do the same as with the pink stuff. Just using spackle can result in shrinkage, and/or it needs to be sanded. By the time it is sanded, the baseboard has been caulked and the dust falls on the fresh caulk. Then there's the risk of messing up the caulk when the baseboard is dusted.
Someone mentioned wiping a sanded area with a damp rag before painting the wall. That will definitely help prevent having to spot prime to avoid dull spots in the finish. If it's a larger patch, it's wise to hit the area lightly in a cross-hatch pattern with a semi-dry brush before painting the entire wall.
