From the article: Engineering: To John Paul Stapp, Edward A. Murphy, Jr (both posthumous) and George Nichols giving birth in 1949 to Murphy's Law, the basic engineering principle that "If anything can go wrong, it will".

I read an article several years ago about the true origins of Murphy's Law. If memory serves, it was in the Smithsonian's Air & Space magazine.

Back in the late 1940s, engineers were conducting rocket sled tests at White Sands Missile Range in New Mexico (and they're still doing them today). After one such test, they found an electrical connector had been reversed, ruining the results. Engineer Murphy noted, "If it can be done wrong, it will be done wrong."

The obvious implication of that observation is that connectors should be designed so they can't be connected improperly. Look at the connectors on your computer like the parallel, serial, monitor, and USP ports. They can't be connected wrong. The people who designed those connectors kept Murphy's observation in mind. That's the way it should be done.

You'd think it'd be both obvious and standard engineering practice to design all connectors so they can't be connected incorrectly, but you'd be mistaken. A couple years ago, an Airbus A-320 airliner nearly crashed on takeoff due to a connector being reversed during maintenance. This is by no means a problem unique to Airbus.