I seem to remember some time ago slave laborers at Peenemunde were passing on information to Allied intel.
In Cornelius Ryan’s “The Last Battle,” he interviewed one of the slave labor workers at a factory in Spandau. The guy was making alternators for panzers. He could easily have turned out 50 in a day, but usually only turned out four, and they were defective. I would imagine most of the slave workers were doing the same.
One of my college roommates got a summer job assembling truck doors at the AM General plant in South Bend. He could easily turn out 40 in a day, but only did that once. That was when the union shop steward told him he was a “rate buster” and made them all look bad. My roomie was told in no uncertain terms that the norm was ten...and only ten.
So apparently the American automobile industry took too many notes from the Germans.