I didn't think the ending of K-PAX was bad at all. Some mysteries are unsolvable, especially through human eyes. Still to this day I wonder, was he or wasn't he? To have that kind of influence years later really says something about the picture. Life is a mess, and not all problems are solved cleanly and conveniently, wrapped up in a pretty bow. That's why I admire the movie. If the ending solved the mystery with a cliche as most movies do, I don't think I would have liked it nearly as much.