The only FTF or functions that I've ever experienced with any S&W revolver (many!) over the past 50 or so years has been ammo related, most often a primer problem or squib load (bid priced practice ammo during training and qualifications). I have known of a very few incidents where an internal part of the action ceased to function properly either due to Bubba-smithing or just plain wear and tear on revolvers that were used to fire multiple thousands of rounds during years of recruit training.
I have also seen a few incidents where either the hammer or trigger stud were broken loose from the frame, usually caused by someone operating the action under full spring tension with the sideplate removed, I think.
I actually purchased a Model 13 with a three inch barrel sight unseen that had this problem. When it arrived at my dealer, I carefully inspected it (no disassembly involved) before accepting the delivery. The action functioned with out problem both single and double action other than the action was a bit sluggish as if the innards needed a good cleaning and relubrication. The gun actually had a pretty decent and smooth operation and the external condition was very good. When I got it home and removed the sideplate, I found that the hammer stud was broken off the frame and that the pin that secured the hand and spring inside the slot in the trigger was also broken and loose in place. I was astounded to know that the action appeared to be in good condition and produced a really pretty good function. I reported the findings to the seller who was unwilling to accept any responsibility for the condition of the gun or make any adjustment for the cost. So I bought some experience and since I really liked and wanted the revolver, I sent it to S&W for repairs. They replaced the broken hammer stud as well as the complete trigger assembly and hand, timed the action and tuned it, and of course, refinished the whole thing since replacement of the hammer stud required refinishing.
The revolver is now is perfect operating condition and shoots well. The refinish was not with the same type of bluing that originally came on the revolver but it is very well done as was the polishing done prior to the rebluing. I've got the price of the gun plus about 2/3's more invested now in it, but given some of the high prices commanded in recent months for three inch S&W revolvers, my investment doesn't look quite so bad. Irregardless, I like it, don't intend to sell it, and I'm satisfied to have it as it is now. I'm still disappointed in the seller, but can't say for certain that he was aware of the problem when he sold the gun to me. I do have my suspicions, but that's another story! In any case, the revolver is now as good as new, considering that it's hard to get the same kind of a bluing job as the ones that came on those fine old revolvers.
I've never owned nor used nor seen any product, especially of a mechanical nature that have been as reliable as the S&W revolvers that were made during the 30's through the 70's and into the 80's. I prefer the older ones, and even the majority of the revolvers produced after this time have a pretty good track record over all. There have been times when quality control slipped, and none of the newer models had the individual hand's on attention of the older model during manufacture. Actually, I guess I have had one product that has been maybe more trouble free than my S&W revolvers, and that is an anvil that has been used for four generations and which I have passed along to the fifth generation.