Why forced labour weakened skilled production

Nazi Germany's synthetic-fuel effort receives limited credit, but its administrative appearance should not be mistaken for genuine industrial efficiency. Forced labourers who were underfed or inadequately trained could not reliably perform complex factory work. Hostile workers could also produce defective components deliberately. Basic construction absorbed large numbers of coerced workers, but the same system was poorly suited to complicated processes or machining. Fuel plants and their machinery required consistent technical quality, which a nominal labour headcount could not provide.