We've all had it happen--we are doing the polite thing by holding the door open for someone, but the person we are holding the door for seems to be taking a really, really long time getting to the door. It's that awkward holding-the-door-for-somebody-who-is-too-far-away situation. Here's a pretty funny video from an Australian comedy show called  "The Micallef Program" describing this same situation. In the video, he talks about polite distances.