They failed because they had to fight in the western front and in Africa too at the same time.
No they did not, prior to Kursk there was no fighting in Western Front and Rommels forces were the size of one undersized corps, if you're arguing that a single small corps would make a difference thats a joke.
hen they first attacked Russia, they were very successful
Because Russia had a sh*tty chain of command, a faulty combat plan and assembled all its forces chaotically and very close to the front, of course they had initial
Fighting on many fronts at the same time and the very cold winter did the rest.
Do you have problems with reading comprehension? In 1941-43 Germany was fighting on ONE front, in Russia.
They also sent DAK into Africa but that was a pathetic five divisions, thats not even 70.000 men.
Zhukov's men hated him he didn't spare them at all, Stalin forced soldiers to sacrifice themselves for gaining a city by a certain date no matter the cost, usually some socialist anniversary.
You just answered yourself, high losses of the RKKA were due to political reasons or HQ indifference, not military incompetence, we're talking about 1943~ of course, prior to that it was incompetence all the way.