The prodigal returned because his father’s servants were treated better than he was living. Had his father excluded any possibility of reconciliation there could have been no return. The prodigal knew he had failed his father but also knew his father would not want him destroyed. His contrition would have been impossible if there was no hope of reconciliation.
Jesus said to the prostitute:
“Neither do I judge you. Your sins are forgiven. Go and sin no more.”
It's more commonly rendered, "Neither do I condemn you," and I think that makes a difference. Jesus declared that He had the authority to judge and to convict. In this case He "judged" that the woman had sinned, but didn't condemn her as beyond forgiveness.
“The prodigal knew he had failed his father”
Whereas today’s prodigals now believe, thanks to the fathers comments, that they were right all along and the father had failed the son.