A vivid panorama of a colossal conflict, told at the strategic, tactical and personal level. Tales of savage fighting and unimaginable hardship. Strictly a military history. That allows the author to ignore all the horrendous killing going on in the rear areas. The studious avoidance is hardly surprising. Carell (real name Paul Schmidt) was chief press spokesman for the Nazi foreign ministry from 1940 to the end of the war. His book seems intended to serve as a memorial for all the German soldiers on the Eastern Front, from the lowliest private to the most senior commanders.
He does allow that Russians often fought bravely and effectively. However, a Russian soldier's diary entry decrying German looting and rape offers the only reference to malice in the wake of the German invasion (even then, looting and rape are mentioned, but not mass murders and attempted genocide); that's offset by several references to ethnic non-Russians or religious communities welcoming the German army as saviours from Communist tyranny. Nor is there any comment about what Europe and the world might have looked like if a few more divisions and several hundred more tanks had been available and allowed the capture of Moscow and Stalingrad and Murmansk.
Carell says in the book that lack of material resources would have prevented an eventual victory even if Stalingrad had not turned into a disaster. There's still a whiff of a longing thought behind the admission: if only the Fuhrer had left the war to the generals. Clausewitz, cited a number of times, would probably have counselled against the invasion but following his principles probably also would have led to more success.
The book was first published in 1963, which meant limited access to Russian sources. Some reviewers describe the book as dated on that and other grounds. I'm insufficiently familiar with the history to comment. However, this book does paint a broad and compelling picture based on information from hundreds of sources. The Nazis had a good military at their disposal, and apparently at least one good writer, even if there are hints of slyness in his work.