My father worked for a defense manufacturer making airplanes and other stuff. One of his first projects was scheduling parts for manufacturing in the late 80s.

They joked at the time they used JIC (just in case) because they had so many random parts with no method to the madness. The scheduler worked out and they were able to move it off some high performance IBM (or similar) computer onto a PC that didn’t require a specialized IBM tech or support contract, written in C.