Why don’t people just get vasectomies and tubal ligations if they don’t want kids?

I was in a pretty serious relationship a while back that ended to a million reasons but one of the key reasons was I didn’t want kids and they did. I wanted to be fixed so I didn’t end up with a bunch of kids that I didn’t want. I brought up the idea of them getting surgery to ensure they couldn’t get pregnant so we can have full free unprotected sex but they didn’t want to do that because of the permanency. What?