Why were Soviet losses consistently so high?

There are different answers for the different operations or battles considered. Since things did not change fundamentally between each operation, I will answer on a more generic fashion.

1941:

A lot of reasons have been explained in other answers. We can summarize them under the following bullets:

• Lack of the Red Army prior to the war: the Red Army suffered from massive military trials for "treason", the Great Purge of 1936-1937. Red army lost there a lot of capable officers and NCOs. This implies lower efficiency in coordination of units, lack of appropriate training. It also had a deeper effect: military commanders were "afraid" of the trials they could come under because of how they commanded. Note that this factor had consequences over the entire war
• Superiority of German Army: a lot of training adapted to doctrine, tactical efficiency and experience

1942:

• This year, all Soviet attacks or offensives suffered from a major problem: lack of firepower superiority, because of shortages of ammo and/or artillery pieces. Add to that that the air force was not always numerically superior (in termes of effective operationnal airplanes) and suffered from technical and training inferiority
• This lack of firepower had a different consequences on the armour and infantry forces: Soviet tanks suffered when attacking German antitank defences, that were mobile in defence and heavy in caliber. Same things or infantry, even more because German made an extensive use of "mottis" (fortified small towns).

Now, you could tell me: ok, but there was the same situation at different times with different ennemies. Yes, but the difference here is that German are very efficient tactically. Even if the Soviets are good as well, the German will force them into a frontal fight and thus losses will be high. Second point, Soviets were not really good tactically: often, lack of training for officiers and coordination led Soviets to attack brutally. Last point, contrary to for example the British that would break attack before taking heavy losses, the Soviets went on until they break (whether through the ennemy lines or break themselves).

1943:

1943 is a special year: it started by a defeat from the Soviets, that went on too fast after Stalingrad. Then pause, and Kursk: special situation where the Soviets had heavy losses because they counterattack or launch counter offensives everywhere: elite German divisions inflicted them losses. The point is that this summer, elite German divisions were elite not only by training, but also by equipment: the Soviets were beaten in the fields of tank and airplanes, and only barely equal in quality of artillery (and superior in quantity). This explains heavy losses.

1944:

The rest of 1943 and 1944 saw massive lffensives. Some succeded, some failed. Both showed important losses, because again the Soviets attacked until they break. More than often, Soviets attacked with a first push: the push was hard, but Germans managed to stop any breakthroughs. Other attacks needed to be made. Depending on the situation and the willingness to attack, three scenarios are possible. Two of them triggeed heavy losses:

• First: launch another attack for breakthrough (using heavy tanks and infantry), but without proper preparation since the situation has changed: losses will get higher and higher, but the speed in re-attacking could offer the breakthrough
• Second: launch the armored push: this is the worst scenario because there had been no breakthrough, so tanks are destroyed by proper defensive positions that offer no way to manoeuver
• Third: launch another attack for breakthrough (using heavy tanks and infantry), but with proper preparation: this is the best scenario

1945:

Similar to 1944. Add that Soviets had no more the advantage of fighting on an amical territory, and moreover they fought on Hungarian or German lands where native soldiers fought desesperately.

Major reason:

• Lack of experienced leadership
• Lack of experienced personnel
• Lack of good equipment. (WW2)

A lot of this had to do with the politics in 1930. During the Great Purge, Stalin either incarcerated or executed many people he didn’t feel were “loyal” to him. In November of 1939 when Russia invaded Finnland, Stalin had done away with a lot of his rivals. This included a large portion of his military command structure. While the Russians had numbers and technology they lacked experience and it caused them to use brute force to push the Finn's back.

“In addition to the so-called show trials, a series of closed trials of top Soviet military leaders was held in 1937–38, in which a number of prominent military leaders were eliminated; the closed trials were accompanied by a massive purge throughout the Soviet armed forces. Stalin’s liquidation of experienced military leadership during this purge was one of the major factors contributing to the poor performance of Soviet forces in the initial phase of the German invasion of the Soviet Union in June 1941."

• Great Purge

In the 1930’s PU-36 was the training manual that was used for battle tactics. Stalin undermined these great improvements made in the Red Army strategy between 1918 and 1939 with this purge. Colin Powell said, "The first casualty of war is the battle plan" and when you don't have experienced troops and commanders it dies even faster.

When war broke out, Stalin implemented a rapid force expansion, a conscription of sorts; this lead to poorly trained units with very inexperienced officers. They used it so heavily that the civilian workforce dropped by 40 to 60%. These two things greatly impacted the Winter War in Finland and allowed the Soviets to be flanked and pushed back. Eventually, Stalin just started throwing troops at the front line and wearing the Finn’s down with overwhelming numbers. Basically, using the tactic of, if it takes 3 of mine to kill one of yours so be it.

In WWII, Stalin didn’t want war with Germany. In an effort to keep peace he would not allow his army to setup proper defenses. This left Russia scrambling to create a good defensive position. During the second day of invasion, Group 10 of the Red Army tried to counter attack but due to jammed radios, no phones, and the Leuftwffe controlling the skies the group was shattered. 4 million soldiers were wounded, captured or killed. This lead to the Russians having to move key factories away from the borders and created manufacturing problems.

“The end result was what seemed like a mass of riflemen without rifles being urged forward in human wave attacks by incompetent generals and political officers”

• War History

These tactics early on in the war caused for a large number of casualties. Come 1941, when the Germans were blunted, the Russians were able to start producing better equipment but still they were limited on tanks and advanced weapons, so divisions were centered around the rifleman to take on the Panzer and Tiger divisions of the German army. The Germans pushed back and nearly knocked the Red’s out of the war at this point. This caused many Soviet infantry men to launch futile counter attacks and when they failed, they would have to retreat without equipment or rifles. But finally, in 1942 the Soviet Army developed an armor-based battle plan called Deep Battle. This was fairly effective against the Blitzkrieg.

With this new battle plan and the Allies kicking in the door on French beaches the two fronts were able to meet in Germany and snuff out the Third Reich.

This being said. In World War 2 there are many misconceptions and some of those are:

1. Hollywood has put into our mind that the officers of the red army would stand behind their men with machine guns to keep a retreat from happening. Some kernel of truth here but not much. There were sever punishments though for retreating.
2. There are some instances of infantry men going into battle without a weapon but again very limited. In fact, while there are reports on it I can't find the battles in where it happened.
3. German propaganda made the population think that the Red army out numbered the German army 20 to 1. This isn't true. You can read more on it here

I would suggest studying Krivosheyev's work for the Soviet losses and Overmans for the German ones. Losses comparison needs to be done with care, as there are many nuances, as such: like counting casualties of the same type (only killed or wounded killed an missing, etc.) on both sides, counting all the allies for Germans, adding up Soviet soldiers who switched sides (Germans didn't count them), separating captured onlу (those were counted differently on both sides).

Krivosheyev's group has not only estimated Soviet casualties, but also German by using captured Reich archives and statistical reports. The number they got in the end was: 7 181 100 irreversible losses for all German units operating in the Eastern front, of those 4 270 700 killed. Axis allies add up 1 468 145 (806 000 of those killed) more to the number. These numbers frequently are treated separately despite the fact that axis allies fought on the same front. Depending on the author, this may cause the confusion and misinterpretation. If one compares only killed German soldiers to irreversible Soviet losses (frequent case), then he would get a huge difference. Example of using different numbers.

At least in the first part of the war (1) we still get a number that favors the German forces. (2) UPD: this is also true for the second part of the war. For the third part there seems to be less data, but then the Axis usually lost more.

On average, the adequate relation between the military losses of the two sides is around 1,3 - 1,6, depending on the assumptions made by the research group.

The Soviets had more losses for several reasons, all of which are huge organizational problems that required years to be solved. I will mention part of them and they are mostly related to the artillery since it causes the majority of casualties on the battlefield.

1 - lack of artillery in Soviet units. For German units it was usual case to call in barrage of 105mm guns. Say the 6th Army had calibers over 300mm. The Soviets routinely used 76mm guns, later bigger ones started to appear in ordinary units. Big calibers were always in the Stavka reserve and used to reinforce very important directions but even those were smaller than the ones Germans had. In other words, in general, the Germans had bigger guns and more of them in the first part of the war.

2 - lack of artillery shells, explosives, gun powders. In 1942 the Soviet gunpowder factories released half of the gunpowder needed by the military. Poor situation was with explosives. This all of course sums together with lack of ammo and lack of maximum weight of artillery barrage as well as time, needed to accumulate that barrage in order to prepare for some offensive. Roughly speaking, for each shell fired by the Soviets, the Germans could fire in return 3 and even more shells, especially if considering bigger calibers. That resulted in an important problem: in the first part of the war the Soviet artillery could not win artillery duel against the Germans. Absolutely no chances at all.

1 and 2 in total result in less guns, smaller guns that can deliver less mass (due to slower shell resupply) to the enemy at a reduced range (due to smaller calibers). The Germans would simply outrange Soviet artillery by utilizing their bigger calibers and suppress it. Then they rip to spreads tanks and infantry. Good example of this is the Sevastopol battle. The Soviets had naval artillery support there and it was a major factor for Soviet troops to hold on for that long. Another examples are Kursk battles South and North flanks. Rokossovsky on the North flank had simply enormous artillery group and narrower front. Here the Germans made the least progress. Vatutin on the Southern flank however had less artillery and wider front to protect. The Germans made more progress here. It must be noted however that they had stronger forces here.

3 - lack of proper towing vehicles for heavy guns. Stalinets tractors had maximum speed when loaded of like 5km\h. And that is everything the RA had to tow anything bigger than 76mm. So trying to catch say Guderian with those 152mm and 203mm guns is pointless. German motorized units had proper support vehicles and could tow any artillery they need at proper speeds, that is at speeds matching those of tanks. Yes, their infantry units used horses for that. In that respect they sort of matched the Soviets. However the Soviets didn't have fully (I mean to same extent as the Germans) motorized units at all. This also means that if some unit is about being surrounded, then it would be very slow to retreat. And even if it does retreat, it would loose all its heavy guns and ammo (which would be then used by the Germans of course).

4 - lack of infantry transport, that had armor and could keep up with tanks. Famous kfz 251 was there for a reason and the Soviets simply didn't have time and capacities to make anything similar to them. That production was planned for 1943.

All four points together mean that tanks would arrive first to the battlefield. Infantry would lag behind due to lack of transports and even if they use trucks (which they had in excess at the beginning of the war), the infantry would still lag behind the tanks on the battlefield. Tanks would drive away from the infantry, get knocked out and then the infantry would get pinned down by machineguns and massacred by artillery. While this happens, the Soviet artillery would still be half way to the battlefield. And even if this whole mass did reach the battlefield simultaneously and the Germans were stupid enough to try to bash against this head on, then the Germans would still win the artillery duel, then cut off infantry from attacking tanks and deal with everyone separately. Although, they more often would just maneuver a bit and avoid such hard spots, preferring to encircle them.

5 - lack of complete, re-organized air force. Means worse recon, less well defined targets for the artillery and even less effective artillery actions.

6 - lack of troops. Unexpectedly, but until 1943 the Germans were outnumbering the Soviets in most battles. They also utilized their mobile units to quickly appear in unexpected areas (that is how Kiev encirclement happened for example (5)) and to create an overwhelming superiority of men (6 to 1 and even more) and material (6th army for example could use 900 tons of shells per day against 400 tons for the Soviets) in the weakest spot. This was very much worsened initially because the Soviet divisions were forced to defend 40km wide front, whereas they should defend only 10km according to the combat manual. In places, where that front is narrower and the Soviets have better artillery support, we see much bigger casualties for the German side. Example - Sevastopol battles.

Commander incompetence as it is described in most articles is a myth or sometimes a deliberate lie. No commander, no matter how genius he was, could instantly turn the tables when facing such odds. However they did invent some clever ways to minimize their problems. But that usually was a workaround, not a solution.

UPD: (1) the Great Patriotic War is separated into 3 parts: 22.06.1941 — 11.1942; 11.1942 — 12.1943; 01.1944 — 9.05.1945.

(2) - table of Soviet losses estimated by various authors.

(3) - table of German losses estimated by various authors.

(4) - shell usage 1 shell usage 2 (c) Isaev. Couldn't find his original post, so this is a link to repost. Same numbers on higher a level for each year of the war. Average weight of artillery shell was 10kg for Soviets and 14kg for the Germans.

(5) - The Soviets didn't want to leave Kiev and there were no indications that they cannot hold. Kleist's 1st tank group made a march overnight that the Soviets considered impossible and its strike collapsed the defense of Kiev. This is a translated talk in the Stavka before that.

Various reasons, from demographics to communist system

• First we need to start with the period before WW1. Russian Empire was mostly rural and agricultural. According to census from 1897, 77.5% of population were peasants, and this does not include Cossacks who were also rural population but with different status. This corresponds well with the low literacy rate of about 20% in the same period. What does this means for the military ? Basically, you have large mass of conscripts only fit to serve as infantry, possibly in some other branches as gun/howitzer loaders, construction details etc ... but nothing sophisticated or overly technical. You would train these soldiers basic drills and commands, and use them in mass, almost like cannon fodder. Of course, those who do survive could become basis for something else. Usually, Russian Army would recruit NCOs from successful soldiers, even giving them some basic education if necessary. But it was harsh selection, and as expected casualties were high.

• Officer corps of the Russian Empire in WW1 was not as good as for example German officer corps in the same war. Indeed, many of them simply came from privileged (noble) families (typical example would be famous general Alexei Brusilov), and acquired rank due to connections and influence. Nevertheless, there were steps to rectify this and educational standards were higher than later in the Soviet Red Army. Russian casualties in WW1 were relatively high (1.8 million dead) but still much lower than in WW2 (at least 8.6 million military dead) . Unfortunately for Russia, large part of officer corps as well as intellectuals was simply killed or at least dismissed by Bolsheviks. Of course, officer corps was mostly on the side of Whites, so this was somewhat understandable from the perspective of the Civil War. Nevertheless, nascent Red Army was from the beginning lacking educated personnel.

• In the relatively short period between end of Civil War and WW2, Soviets were trying to train new generation of leaders, and to transform Red Army from traditionally pattern of peasant infantry army to a modern mechanized army. It should be noted that this was often done "artificially" . Communists were as a rule obsessed with numbers. We have thousands of tanks, airplanes etc .. More subtle things like quality and training of the crews, command & control, and especially logistics, were often swept under the rug . This lead to a situation when you had thousands of tanks at the beginning of the war, but many were actually broken, others didn't have enough fuel, ammo or spare parts, or even trained crews. Same happened with airplanes and VVS, heavy artillery units and any technical branch except perhaps the navy (which was somewhat separate organism and largely left to its own devices). You could call it number's paralysis where paradoxically units that had more equipment fought worse than those units who had fewer tanks, airplanes or guns, but had more time to master their employment in real life.

• Of course, we must mention Tuchachevsky Affair and subsequent Purge of The Red Army . No matter do you believe that Tuchachevsky really planned to topple Stalin, it must be said that this event simply erased much of what was accomplished in short 15-20 years of Red Army existence. Many of the senior and medium level commanders were dismissed, sent to GULAG or simply killed. Spirit of indecisiveness and fear permeated trough remaining ranks, and in the worst possible time when the Red Army was expanding expecting coming WW2. As a consequence, many units were commanded by junior commanders promoted beyond their abilities and knowledge, and even worse lacking the initiative to make decisions by themselves, and waiting for the "orders from above".

• Finally, it must be said, Wehrmacht had no equal in 1941. German Army (Heer), supported by Luftwaffe, was simply best in the world at that time. When Barbarossa started and in first few weeks of it, many were simply considering that USSR was done for. French (one of the best armies before WW2) were quickly defeated, British were trashed and saved by the sea and naval power, smaller countries (Poland, Belgium, Netherlands, Norway, Yugoslavia, Greece ... ) were all quickly overwhelmed. German war machine seemed unstoppable and frankly it is a miracle that Soviet Union survived at all, mostly due to resiliency and stoicism of Soviet people.