Does it happen to some of you sometimes.
I have been gigging professionally for [checks calendar] 50 years, and in all that time I have never broken a string onstage or in the studio*. And, fwiw, the few times I felt it was prudent to bring a backup bass, I never needed to use it.
*Come to think of it, in those 50 years I have only ever broken a bass string once. And that was because I was trying to burn off some extra silk windings with a lit match.