Murphy's Law trivia

"Murphy's Law" is maybe the best example of a specific, technical concept which has been broadened and taken out of context. There's some debate on the origin of the idiom, but the story I like is that it was invented by a aeronautics engineer working on the space program. He was working with a group, building a high-G centrifuge-like device. When they ran the device, there was no reading on the sensors designed to measure the G-force. And when they investigated that oddity, it turned out that the sensors had been placed inside the device backwards. He said something to effect that if you make something that can be assembled incorrectly, someone will eventually assemble it incorrectly. That's a good point. And one that informs a lot of current engineering. These days, I notice that most of the stuff I buy with some assembly required has little grooves on the pieces so that it's impossible to assemble incorrectly. If I understand the original correctly, that's the result of "Murphy's Law". It's less a statement of infinite pessimism, and more a statement about probabilities and planning, not for the "average" case, but for the eventual worst case.