Why do some states have no fault divorces?

[Anonymous]

If somebody commits adultery and leaves you, and you are the higher earning partner, why do you owe that person half of your stuff? You didn’t break up the marriage. They did. So clearly they are at fault.

[Guy13]

It does not make sense but this is what a prenuptial agreement is for and if you have two reasonable people then both are eager to sign it.