Once upon a time there was an elderly man who lived in a small, high rise apartment in busy downtown New York City. Whenever it snowed, he made his way down to street level with his old shovel and he cleared the sidewalk of snow and slush. A curious passerby asked why he always shoveled the sidewalk.
After all, it wasn't his job.
The old man replied, "Watch the faces of the many people who walk here. Before they get to the sidewalk that is cleared, they are looking down and walking cautiously. When they get to the cleared sidewalk, they look up and walk with a little joy. That's my job; to help people look up and walk with a little joy."