It is so easy in our rushed and busy culture to resent interruptions. Here is a very different approach:
I remember my mother telling me when I was very small that we must always be kind to strangers and unexpected visitors because you never knew when such a person might be an angel. I don't know if she really believed that or not but I do know that one of her highest values was that of hospitality.
I recall the story about a man whose path was the act of greeting people. Whenever there was a knock on the door he would say, "The Lord is at the door."
— Donald Altman in Art of the Inner Meal