Never say never. I've seen a spoke break in the middle before, and
it makes a pretty spectacular noise. The culprit was corrosion,
probably started at a surface scratch.
Sorry, I assumed stainless, I've long discarded anything that isn't. I've also
had a few fail where they were nicked by a chain, but I thought the topic was
fatigue, not accidents or rust.
Stainless steel isn't immune to all forms of corrosion. Depending on the
grade, stress-corrosion cracking, usually associated with exposure to
chlorides (i.e, sweat or salt air), is a common failure mode.
Chris Neary
"Science, freedom, beauty, adventu what more could
you ask of life? Bicycling combined all the elements I
loved" - Adapted from a quotation by Charles Lindbergh