Not a question you can answer shortly, really.
The German production was at its highest in 1944, I suppose somewhere June-Aug 1944, in almost all areas ;planes, tanks, ammo,artillery etc.
The German arms production was even being closed down in 1941 as it was considered the war was over, which was more of a political view, I guess. But the fact is that production did not meet demands and the German attack especially in Russia suffered from this that year and later.
One reason next to the "war is over " theme was the German attitude of women not sent to work, they were meant to be house-wives instead. Also the "fun and games" were there for the ordinary people, dog racing, zoos etc that raised the morale of people. Keeping this cover up meant that a huge amount of possible workers did not take part in the arms production in Germany until late in the war. Mostly this took place after Stalingrad and the Göbbels´ call for "Total war".
Of course bigger numbers of slave workers were brought to the country (=Reich) so that also this increased production figures after 1942.
It seems Speer was one of the key figures to make the production go so high but cannot be sure how well for instance Todt would have made.
It´s hard to say whether bigger production figures earlier would have meant different success in warfare for the Axis, but at least I´d think the war would have lasted longer.
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