These following two stories are true. In their aftermaths, I really found myself wondering about the thought processes by which I had been confronted.
Case 1:
I'd made a prototype model of an RF amplifier which was housed in a sheet metal enclosure and that amplifier was working pretty well. One day, I took it from the lab over to my desk and left it next to my phone while I attended to some other matters. When I got back a few hours later, the amplifier was gone. Someone had taken it away and left behind no note or anything else. I had no idea what had become of it and yet I still needed it.
A week or two later, I spotted my amplifier on somebody else's desk roughly four cubicles away and it (the amplifier, not the desk) was piled to the rim with cigarette butts, ashes and used matches. I spoke to the guy whose desk I'd come to and he said "Oh yeah. I thought it was an ashtray and I needed one."
Smoking was allowed back then.

I told him it was an operational engineering prototype, I took it back, I spilled out the debris, I used an air hose to blow out the remaining dust and then, back in the lab, thank goodness, it still worked. (Whew!)
Case 2:
We were buying wideband transformers from this one supplier and some of the received units did not work. We decided to make a test fixture for Incoming Inspection to use and when the next shipment arrived, the test fixture identified several transformers out of a fairly large lot that were no good. Those that were tested as good later worked well in their intended application which just happened to be the above amplifier.
A couple of months later, another shipment of transformers arrived and I got a phone call from Incoming Inspection asking me what they should do to test the newly arrived stuff. I said to use that same test fixture just as before, only to be told that the fixture had been taken apart because its components were needed for a different project.

It took me a few minutes to process that input.
I cobbled some various stuff together to make another fixture and we got that second lot of transformers tested too. Just like before, some of them were bad and those that tested okay worked properly when installed in amplifiers.
Shortly afterward, I left the company. Sometimes I wonder what happened after my departure.