Does forcing an absentee parent to GIVE UP their parental rights, accomplish anything?

I hear a new trend emerging, forcing the absentee parent to give up their parental rights because they WON'T pay child support or parent their child...when there's no NEW parent waiting to adopt your child, and you'll still be a single parent. What is the purpose of making a DEADBEAT parent relinquish their parental rights? And what will this accomplish for the child? The definition of a legal heir. My 30 minute commentary exploring this topic.