I can understand Hitler's point of view in here. Take in consideration that:

-Stalingrad, since August until November 1942 had costed 100.000 casualties. So, if you go back, those 100.000 men have died for nothing?
-You are completely sure, because you have been told by many people that the pocket can be supplied by air.
-You thrust the men and you are convinced that if they have supplies enough to hold on in the winter, you can save them in the spring.

That was all wrong, but those factors were very important at that time.

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"War is less costly than servitude, the choice is always between Verdun and Dachau." - Jean Dutourd, French veteran of both world wars

"A mon fils: depuis que tes yeux sont fermes les miens n’ont cessé de pleurir." - Mère française, Verdun