Lack of bonding isn't just peculiar to those who've been adopted.It can happen,,and does,with birth parents,depending on the nature of the mother and also circumstances involving the birth itself,,so it's a myth that adoptees don't have any bonding.
Some mothers have had children as being a right of passage,something which is thought of as the thing to do,without further thought of any future implications. Thankfully it doesn't happen that way so much as the years have gone on and now women have a choice,,to have a child,,or not to have a child.
It's what the grounding consists of while the child is growing up that seals the fate of a childs' future.