If you drive your car off the road in a mountainous region of the US, there is a very good chance that you will hurt yourself and/or damage your car. Scientists can predict this statistically. What scientists want to be able to do is predict exactly which rock will kill you or break your axle. They can’t really do that yet except to make statistical guesses about how much more likely the crash was on the road vs. off it. But we’re heading into increasingly rough country, so please let’s all try to stay on the road.