For the rank-and-file, the motivation was quite stark, in the words of Fedor von Bock, the commander of AGC (Army Group Center), in reply to his subordinates when the Soviets launched their counter-offensive at Moscow in December '41: ‘either one held out or let himself be killed. There were no other choices.’

The dimensions this threat could take are illuminated by Helmuth Stieff in his diary: 'We have launched this attack largely with infantry regiments and can give them little tank protection. Our high command has urged us forward with an almost unreal sense of optimism. I instinctively feel this cannot work. We have assembled everyone we can find, even bringing up security detachments and putting them in the front line. These men are unsuited to intense combat, and when their commanders were killed in the first hour of the offensive, the rest refused tocontinue. They have been driven forward only because our artillery units threatened to open fire on them.'

Refusing orders or just expressing 'defeatism' were capital crimes in Nazi Germany; nevertheless, when Barbarossa went wrong there were some serious issues with morale, and effective mutiny (such as units refusing to attack). Even after the war, many of the German commanders responsible for this fiasco still felt fit to place the blame on their peers who retained enough common-military-sense (principally Kluge) to show a bit less than unbridled enthusiasm for orders from the high-command, who were woefully out-of-touch with the men fighting in the field.

Why did the high command completely abdicate rational military doctrine, and embark on a (in hindsight) entirely suicidal course of action?

David Stahel offers a speculative, but plausible explanation in his book The Battle for Moscow (and I quote at length here for 'brevity'):

'It was as if the appalling condition of the German troops, the freezing temperatures and the Red Army were all entirely extraneous to German strategic direction; it was as if the generals themselves could lose the battle through blunder or miscalculation, but that it was entirely their battle to win or lose. Deciding not to halt the offensive was therefore a decision not to accept defeat and thus maintain the prospect of victory. Such a conceptual framework almost seems too flimsy to be credible, but one must not forget that the whole German command had for weeks supported an offensive that, even before it began, made little practical sense. Now on 4 December the ambiguous concept of German success can perhaps no longer be understood in any normative sense – if it ever could be in the course of November. Here our understanding requires a transition from the physical to the metaphysical world, something that defies the usual interpretative framework of military histories. With incontestable evidence linking the Wehrmacht’s top leadership to the Nazi cause and its ideals (as research into the war of annihilation has shown), one may well begin to enquire just how far the Nazi worldview informed the generals’ judgements in strictly military matters. In other words, if National Socialist thinking had already convinced the generals to partake in blatantly criminal matters, how far did this same corrupting phenomenon impact their direction of military campaigns? Certainly, there are no easy answers, but already in 1941 one can identify central tenets of the Nazi worldview impacting decisions. Emphasising the primacy of ‘will’ in the achievement of objectives would be one example, just as the ardent adherence to an Endsieg in early December 1941 would be another. In spite of the prevailing circumstances, which seemed to demand a cessation of the attack, the absolute refusal to stop the offensive and concede defeat was an end in itself. It served to avoid defeat and maintain the chance of victory; an objective requiring no more tangible goal or recognisable aim. It certainly did not need to be considered in any other strategic context. Thus, the question of what the German command hoped to achieve on 6 December is moot because they were not focused on a goal that we can measure. The principal aim was to remain on the offensive; that alone promised victory without any further need to consider how that might be obtained. From a contemporary perspective such a viewpoint makes little sense, but in context of National Socialist military thinking there was no discussion about it, unless, like Kluge, one was seen to be opting out of the maximum commitment to victory, which alone allowed defeat.'