no prisonners taken : this is not correct :in 1941,3 million Soviets became POW and ,after the encirclment of Stalingrad,more Germans were taken POW than were KIA/DOW .
that was an exaggeration. i was describing the fierceness of the battle. of course there were prisoners. in operation barbarossa alone, one encirclement near kiev captured 750,000 soviet soldiers. 90,000 germans were taken prisoners in stalingrad (but very few, if im right, around only 6000 were able to return to germany. POW treatment on both sides violated international war protocols).
despite this, the bloodbath was still too much such that its as if the policy was to give no quarters, to take no prisoners.
To highlight he fierceness of the war in the eastern front, one must know how good the wermacht was during WWII. It was the master army of the world. In europe, it was unbeatable. It invaded poland, the scandinavia, france, belgium, netherlands, and drove out the british forces without much trouble. Next, it went to yugoslavia, and greece and conquered in a matter of weeks. it again drove the british forces out and establish itself as almost an invincible force.
However, it never faced serious resistance until it launched operation barbarossa into the soviet union. Hitler was expecting a quick victory (a matter of one year. He increased the force of the army into four million men, and sent 3 million of them into the eastern front. Despite this, the Soviets did not collapse unlike the rest of europe. Suddenly, death tolls in the wermacht rose to unprecedented levels (although the soviets had much higher casualties). And for the first time, Germany tasted defeat at the gates of Moscow.
Germany would try again and raised an even larger army the following summer with operation blue and wreck the greatest amount of havoc in the course of the war (russians called this black summer) but at the end, Germany would again be stopped in the city of stalingrad. the next attempt was operation citadel which would be quickly stopped at kursk. From then on, germany would be on the defensive and chased back to berlin.
If the previously invincible wermacht was getting into such kind of trouble despite the increase in its size and greater commitment to war by its citizens, then you know soviets must be giving it a very fierce battle, something that the rest of the world could not deliver.