Why is enjoying sex a value we want to keep, while enjoying punishing is a value we don't want to keep?

I upvoted Eugine_Nier's reply, but I think in current mainstream western society it's because enjoying sex superficially looks like net positive (though it may in some cases be net negative), while enjoying punishing looks net negative. And historically there certainly is no shortage of groups who tried to remove their valuing sex, I wouldn't be surprised if the total number of people who tried that exceeded the total number of people who tried to make themselves not value punishment.