The myth is not of Hitler's making, though. It was peddled by Ludendorff and others at the end of the war to deflect blame. The German public was kept unaware of the disastrous state of the army at the end of the war as well as the fact that the state finances had been run into the ground. Going all in the German government had also taken on huge debts which they only realistically could repay if the war was won and they could have France, Russia and the UK pay war indemnities. This was a failed gambit that proved to be extremely costly.

Edit: typos (thanks autocorrect).