If you find it in a bad boy, then you usually sleep with him. It's like marrying a pit bull. They are great for what they are, but I can't imagine why you would marry one. By definition, a bad boy is a bad husband. You say most people don't get good at relationships until they're over 40.
People take a long time to get smart about everything.
The areas in which we have prodigies are usually math and music. And those are the only two areas in which people produce most of their great work before they're 30. So it s no surprise that if you're a reasonably intelligent person and you're paying attention, then you might make a better choice when you're older than when you're younger. If you look to the right of you and you look to the left of you, you will see people who make mistakes in their relationships, and all you have to do is pay attention. Mainly, I think people are afraid.