Laban did not just separate the flocks. He placed three days of walking between them, a buffer wide enough that no marked goat could wander home by accident, no hopeful lamb could find its way back to Jakob's care (Genesis 30:36).
What did Targum Pseudo-Jonathan say Jakob was left with? Not a respectable flock. Not even an average one. He was left with the old and the feeble which were left. The leftovers. The ones nobody wanted. The animals that a herdsman hands to an enemy when he wants him to fail.
This is the quiet shame buried in the story. Jakob, who had asked only for the oddly-marked, was given the elderly and the limping. If anything was ever going to multiply from that flock, it would be a miracle, because the biology of the situation guaranteed nothing.
The Maggid teaches: heaven often begins its work with whatever nobody else will claim. The old, the tired, the rejected. In the hands of a righteous shepherd, even those become the starting point of a fortune.