Well, you prove my point. It's not likely that someone is going to get hit by lightning but everyone knows not to stand outside under a tree during a lightning

Well, you prove my point. It's not likely that someone is going to get hit by lightning but everyone knows not to stand outside under a tree during a lightning storm. Similarly, a man should not be alone with a woman he isn't married or related to. When something has low probability, high risk, and is easily avoidable, you avoid it.