In German manufacturing, Werkerselbstprüfung means worker self-inspection. Der Werker, der das Teil produziert, prüft es selbst. The worker who produces the part checks it himself. One definition states the rule in four words: Kein Weitertransport ohne positives Ergebnis. No onward transport without a positive result. The worker is to sign the check with his name. The method arose in the mid-1960s, and the trade journal Produktion calls it disputed.