Who made it as a law or what?

It was necessary to make it criminal because other methods didn't work to get parents to pay. If they dont' pay, the child ends up in poverty, often supported by the state. The father shouldn't be able to get away with that. The law would have been created by the lawmakers.

Child support is adjusted by income. If a person is not able to pay because they don't bother to get a job is very different than someone who can't pay because they are truly unable to pay. The court knows that and usually responds accordingly.

Legal standard by common law is that a father has responsibilty to a child. That should not be hard to understand. Someone "don't wanna pay" is bull. No guy wants to pay for a kid. It isn't his choice.

Courts order fathers to pay support. The reality is that many guys try to squirm out of it, thus, states passed laws to enforce it, by the consequence of being arrested. Failing to pay support is a defiance of a court order.

The amount of support is based on the proven earnings of the father. Yes, it is hard for some.