Several generations of welfare teenage mothers popping out baby after baby with no responsible adults to raise, guide, and mentor the children. It is a fact that the way the child will go in life is imprinted in the first 3-4 years.
Drugs, alcohol, domestic abuse, absent fathers, living on government handouts instead of honest labor, and every other facet of ghetto life.
If scientists tried to design a system that would garantee criminals with no concept of right and wrong, no moral compass, they could not do any better than what the government has created.
This behavoir is perhaps limited to this class. Two parent households where the child is encouraged and helped to get an education and do good in school do not seem to turn out the same way.
But with 75% of black births being out of wedlock these days the future looks increasingly dim.