Tim Wescott writes:

I know that the British had a problem with artillery rounds during
WW-I
(which I believe they solved), and Stephan Ambrose talks about how
German artillery rounds were often duds during the allied invasion of
Europe (and since I have the second edition, includes a letter from a
former Jewish slave laborer, who was one of many that would
intentionally sabotage munitions -- I don't know that I could ever
muster the courage to go to work every day, and quietly engage in
behavior that would have my employers making me wish I were dead long
before they killed me).

Quiet, unsung, unrecognized, unrewarded hweroism. I don't know that I'd
have passed that test either.
--
As we enjoy great advantages from the inventions of others, we should
be glad of an opportunity to serve others by any invention of ours;
and this we should do freely and generously. (Benjamin Franklin)