>>36693
I think part of it's relative, all nations had a build up so Germans may have felt like they were underperforming when they really were not. Also it may be based on what was being told to them or what information was circulating at the time. I remember reading about it in Guderian's memoir, he was complaining that production was shifting back to civilian goods after the French campaign and mentions the Speer miracle and how he increased production by getting factories to work harder and that when he took the position Speer would visit factories and they would not even be working.

Whether or no this is true(it probably has some grain of truth, there probably was at least a factory that went back to civilian production and a factory that was not doing much) these are more or less anecdotal cases and it may be that for most factories this was not the case, only soldiers on the ground would feel like it was(probably thanks to Speer)and that seeps into publications like the aforementioned.