The biggest unanswered questions in movies that will never be resolved

Everyone loves a mystery, but with one big caveat: most people like answers, too. And yet, some movies don't provide them. Sometimes, crucial scenes end up on the cutting room floor, leaving a mystery unresolved. Occasionally, a writer or director purposely leaves a question unanswered, encouraging the audience to reach their own conclusions. Maybe that dangling plot thread is just sloppy filmmaking, or maybe the answer just isn't important.
None of that is going to stop audiences from wondering. The following questions have been bugging cinephiles for years, but don't spend too long looking for solutions. If they haven't been resolved by now, they never will be. Don't waste your time.