Soviet Union (per Glantz who had access to Soviet archives) lost 14.5 million soldiers, and over a million second lieutenants. Who gets to be a 2nd lieutenant? A bright young man with potential for responsibility.
One reason the number of Soviet Second Lieutenants lost during WWII is important:
Soviet doctrine called for officers at all levels, who had absolute control and knowledge of tactics, communications, strategy, logistics, etc. due to political considerations.
Senior non-commissioned officers in the Red Army were barely more capable than junior non-commissioned officers, who themselves were barely more knowledgeable (or reliable) than the conscriptees. Those conscriptees who survived battles, AND were vetted and recommended by the ever-present Political Officers, would then be considered for promotion to higher ranks.
In the Red Army, the ability to quote Party doctrine was more valuable than the ability to shoot straight.
Therefore, Wehrmacht tactics called for quickly identifying and targeting Red Army officers, confident in the belief that this would make an unit little better than a gaggle.