E.g. I'm sure tourist issues when travelling to North Korea are vanishingly rare, and yet I bet I'm pretty good at guessing what not to do. You can glean that kind of thing from the totality of your experiences and knowledge without necessarily testing it.
That's not to say I wouldn't be over-cautious or that I'd be a perfect predictor, but that's just about the looming cost of a false negative. I don't think it's rationally faulty or circular to just act in a self-preserving and overcautious way.