How many times have you opened an ‘nos’ box and found scratches or defects on the part? My dad worked at Buick Fisher Body Flint (53-58) said a lot of ‘cars’ ended up in lot out back with bad parts needing replaced. There was no time to fix-replace going down the line. He was told parts that didn’t pass were inspected, went back into inventory or if too bad back to manufacture for credit. This was at a time when 1/2 cent meant something and all those parts are paid for up front so the bean counters find a place.