https://www.newyorker.com/magazine/2018/02/12/why-paper-jams-persist
I had a short stint as a Xerox repairman in the Navy (far too many fearful hours in USMC choppers because of this, landing on everything from Frigates to Carriers at sea). My number one problem was jams and the number one cause was bad paper.Building 111 on the Xerox engineering campus, near Rochester, New York, is vast and labyrinthine. On the social-media site Foursquare, one visitor writes that it’s “like Hotel California.” Conference Room C, near the southwest corner, is small and dingy; it contains a few banged-up whiteboards and a table. On a frigid winter afternoon, a group of engineers gathered there, drawing the shades against the late-day sun. They wanted to see more clearly the screen at the front of the room, on which a computer model of a paper jam was projected.
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Unsurprisingly, the engineers who specialize in paper jams see them differently. Engineers tend to work in narrow subspecialties, but solving a jam requires knowledge of physics, chemistry, mechanical engineering, computer programming, and interface design. “It’s the ultimate challenge,” Ruiz said.