The centralization of authority was also a fatal flaw in German command doctrine. Unlike the independent authority Allied unit commanders and even noncommissioned officers had to alter or even abandon operational plans in the face of tactical needs, the German High Command often limited their commanders by requiring personal permission from Hitler or other superiors in order to gain needed units or supplies. The Allies could often adapt to changing battlefield tactics, while the German officers could not.
In the orgy of violence that was perpetuated by the Nazis, the Gestapo or SS units like the Einsatzgruppen committed many atrocities. The Wehrmacht was not blameless; except for North Africa, were Rommel personally forbade reprisals, Germany Regular Army units shot and killed civilians and POWs in every theatre. The Wehrmacht was especially vicious in the Eastern Front.
Hitler, disdainful of the professional soldier, often overruled his commanders and sacked them for spurious reasons. After the July 20 plot to assassinate him, tens of thousands were executed or forced to commit suicide, including the able Generalfeldmarschall Erwin Rommel.
In 1944 the huge manpower losses forced the drafting of thousands of young and old men into Volksgrenadier divisions that were under strength but had additional automatic weapons and Panzerfaust antitank weapons. They were the only men left available to replace the huge losses at Stalingrad, North Africa and elsewhere. Even the SS, which required applicants to prove they had Aryan lineage before joining, accepted men from all over Europe by the end of the war.
In the end, with constant air attack, huge armies with superior technology on both sides, the professional army of Germany tried to defend her own borders. But without the ability to produce enough equipment, with millions dead, the Wehrmacht ceased to be the vaunted fighting force of legend.