Taking tests and waiting with hope for positive results is a stressful activity that most people perform only when absolutely necessary. For wire-harness assemblers, it’s a daily challenge.
During assembly, they’re required to correctly insert one wire into the corresponding connector before they can go on to the next wire. And after building the harness, the assemblers are hopeful that electrical-test equipment will tell them the harness is error-free—even though they may find out that the harness has failed.