In the end, the whole operational plan was catastrophic anyway - kick the door in and the whole rotten construction will fall in. Except there was no plan in case that the Sovjetunion somehow didn't collapse.
Operational plan was to destroy Red Army in invasion. And, frankly, they hot rid of 5 million enemy troops and awful lot of tanks, planes and such. They essentially destroyed what was Army in the 1941.
They didn't expect a few things however - larger amount of Soviet troops, inability to get rid of Red Army at once (so that in one moment there would be no opposing resistance, like in France after Dunkirk) due to them giving up land more than getting destroyed (and Kiev battle and a few episodes like it being mainly Stalin's mistake), supply issues in late 1941, etc. With landlease it got much worse - since Allied supplies allowed Soviets to suffer way less from a lot of critical problems (food issues, lack of radios and a lot of other things) and stand up to German Army much better, making the supposedly rotten structure far more durable.