Brown M&M Test

At the zenith of it's popularity, the band Van Halen gained a reputation for being temperamental, entitled jerks who would berate the venue staff for not catering to their needs and desires. An article in Rolling Stone profiled them, and quoted a venue support staff member claiming that Eddie Van Halen had berated everyone because venue staff had left brown M&Ms in their M&M bowl.
Decades later, in another profile, David Lee Roth (their future front man) explained another side to the story. They were a successful rock band playing to large crowds, who would often pile up next to the stage. And they were the first stadium rock band to put on expensive, and dangerous, pyrotechnics -- explosions and streams of fire and fireworks went off on stage, close to the band and close to the fans.
They wanted to make sure no one was hurt at their shows. So, they had about twenty pages of detailed specifications on how the stage needed to be set up, which was in an extremely long "rider," part contract and part checklist. If everything was set up correctly, they were assured no one would be hurt during the show.
"Van Halen was the first band to take huge productions into tertiary, third-level markets. We’d pull up with nine eighteen-wheeler trucks, full of gear, where the standard was three trucks, max. And there were many, many technical errors, whether it was the girders couldn’t support the weight, or the flooring would sink in, or the doors weren’t big enough to move the gear through. The contract rider read like a version of the Chinese Yellow Pages because there was so much equipment, and so many human beings to make it function." -- David Lee Roth
However, their tour bus often pulled into their venue about one hour before their show, and they had to get dressed and ready in that time period. There was no way for anyone in the band or the band's staff to go and check every detail in the time they had.
So just as a little test, in the technical aspect of the rider, it would say 'Article 148: There will be fifteen amperage voltage sockets at twenty-foot spaces, evenly, providing nineteen amperes¦’ And article number 126, in the middle of nowhere, was: 'There will be no brown M&M’s in the backstage area, upon pain of forfeiture of the show, with full compensation.’ "-- David Lee Roth
They needed a way to figure out quickly if the venue staff had followed instructions to the last detail. If they could assess that the venue staff were not perfect quickly, they could reasonably postpone the show another hour and a half or so, obviously frustrating fans, to do a security check themselves.
They chose to include a small, fine print footnote to a clause saying that the band wanted a bowl full of M&Ms on a table right as they entered the door to the menu. The footnote read "Remove all brown M&Ms." [1]
So, they would walk into a venue and immediately check to see if there were brown M&Ms. If there were, they knew they had to delay going on stage while everyone went around and re-checked every detail of the equipment that was involved with their show. And, yes, they berated people along the way.
Thus, the Brown M&M Test became business folklore on how to check to see if things are set up and maintained with adequate precision.

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