I have never had a failure with one of my Smith & Wesson revolvers. However, that is in part because I keep my revolvers in proper condition, and I'm qualified to do so.
I have, on the other hand, fixed Smith & Wesson revolvers for others on many occasions. By far, the most common problem has been either an extractor rod that had become unscrewed (makes opening the cylinder difficult and, ultimately, causes the cylinder to freeze) and accumulated crud under the star (ditto).
The second most common problem I've encountered involves someone deciding to do a DIY detailed disassembly and then messing up the reassembly. So long as they didn't distort the sideplate (by prying), an easy fix.
In a somewhat different category, I have observed revolvers that have been abused. Either I've been asked to do an inspection of someone's potential purchase of a used revolver or I'm looking at one I'm thinking of buying myself. In this category, and putting aside cosmetic issues, observed problems have been bent extractor rods (comparatively easy fix), distorted cranes (a more complicated fix), damaged forcing cones (needs rebarellling, which I don't do), deep flame cutting of the underside of the top strap (not repairable), excessive end shake (comparatively easy fix), and out of timing (ease of fix depends on the reason for the problem).
What do you conclude? If you know what you're doing, keep up with maintenance, and eschew using your revolver as either a hammer or pry bar, Smith & Wesson revolvers are incredibly durable and incredibly reliable. On the other hand, anything can be abused.
Looking at the other side of the coin, I've been asked to look at autos with problems. Once again, two causes are most common: improper cleaning and lubrication of the slide/frame interface (autos are sensitive to the right degree of mechanical impedance between the slide and the frame) and magazines (usually mangled feed lips). It is worth observing that Smith & Wesson revolvers are immune to either issue.
Last point: many years ago, I was asked to witness/document a test. A plastic bucket was filled with a couple of inches of wet mud. A loaded Model 10 was laid on top of the mud, and then a couple of additional inches of mud were poured into the bucket. The bucket was then put aside for a week. When taken out for inspection, the bucket was upended, the mud "cake" given a whack with a hammer, and the revolver retrieved. The only "maintenance" done was to clean the mud out of the bore (for safety sake), and then the revolver was pointed down range and the trigger pulled. On the first pull, the revolver functioned but the round did not fire. (It had a good hit on the primer, and we decided that the primer had become inerted by moisture.) On the second pull, the revolver fired. Ditto the next four pulls.
I can't say that no auto would have passed the same test (though I'm skeptical), because I've never witnessed an auto subjected to the same test.
