Similar question was asked several times in the past (me included), but it was rarely answered (I might be a bit biased).
Here is the answer from /u/mithie007 :
https://www.reddit.com/r/AskHistorians/comments/diconi/during_operation_barbarossa_the_soviet_union/f3wdox0/
And another from /u/treebalamb, from related question:
https://www.reddit.com/r/AskHistorians/comments/23kq8x/during_wwii_what_was_stalins_plans_for_if_the/cgyj6ke/