Being kept waiting. Never knowing when transport will arrive

So there you are in that supermarket queue. You know, the one that stops when all the others have continued. So you decide to change queues, only to find that the one you get into then stops and the one you just left has now started again, and the person who was previously behind you is now getting served before you! Imagine the angst generated, yet in reality in such a situation we are only losing about five or ten seconds.