It is perhaps sad to say, but when passengers who are travelling to other parts of the world leave their passports behind. Then they remember as you are about to drop them off. I know they get stressed and I sympathise that. However, I, in some ways I love it, because I have to bring them back and take them to the airport again. That is a double whammy, isn't it? I had a passenger who paid me three times more than he should have done. So he was not happy but I was the winner of that human nature.