A related trick for predicting the future; things that everyone is worried about are likely to get solved. It is the stuff that people dismiss as impossible that is scary, because when it happens everyone is caught out in the same way at the same time.
That also leads to a decent heuristic for figuring out if someone is overconfident: listening to see if they can articulate a thoughtful list of things that could go wrong. If they don't have such a list then it is likely they won't have countermeasures in place when something goes wrong and will fail for no good reason. Or worse, they won't pick up on the early signs of failure when there is still time to react and salvage the situation.