After 40 plus years of shooting I’ve never seen a spring in a S&W fail.I’ve got Mauser rifles that are 100+ years old and never saw a spring fail on them either.
The only failures I’ve had in an S&W revolver were unburnt powder under the extractor star causing it to lock up (Unique powder) and a pre-1961 ejector rod backing out and locking things up. In 1961 they changed them to a left hand thread to prevent that.