Paul R ZARTMAN,
It depends on the gun and what you want it for.
I have found a number of guns just perfect the way I bought them, though they may not have left the factory that way. On the other hand, I have left my BERETTA 92's, 96's, SIG 225, 226, 232's and 365 just the way I got them. Same for my SPRINGFIELD ARMORY XD9 Sub-Compact. They all work fine and do exactly what I want them to do.
I have had action jobs done on most of the revolvers that I bought new because many triggers were just not good enough, in my opinion. I have bought a number of used revolvers because of the smooth trigger, like my well used pair of S&W model 15 revolvers. Both were ex-prison guard guns and looked awful with their I.D. numbers scratched onto the sideplate, but they both shoot excellently and have very smooth triggers.
S&W generally does a good job, but not always as well as I would like.
RUGER trigger pulls are useable most of the time, but not what I want, with the exception of the MATCH revolvers. I have bought an sold a number of RUGER Security Six revolvers and all those I kept had good, smooth triggers, either from continued use or an action job done the previous owner. They may have come from the factory with a good trigger, but never bought a new one.
I have an old DAN WESSON and the trigger is smooth, but heavier than I like.
A COLT Official Police is a safe queen because of the action, yet the new COBRA'S, KING COBRA'S and PYTHON'S that I have handled are fine the way they are.
Jim