Hard luck is when something great escapes you; love, fame etc. Example: Person A: Did you go out with that guy? Person B: No, hard luck! He said that he was busy. Bad luck is when something terrible happens to you ; car crash, house fire, job loss etc. Example: Boss: Why are you so late to work? Worker: A car crashed into the back of my car. Boss: That's bad luck, are you insured?