Krishna explains the mechanism. Taking hold of his own prakriti, he sends forth this entire host of beings — again and again. These beings are helpless in the matter; they come into existence under prakriti's power, not by their own choice.
This is not a punishment. It is simply how nature works. A seed does not decide to sprout — the conditions bring it forth. Beings emerge because prakriti's momentum carries them. Until a being rises above prakriti's pull, the cycle continues.