Here's your sign

A man walking down the street late at night noticed another man on his knees under the streetlight, obviously looking for something. " What is it you've lost?" The passerby asked." My watch," the man answered. " It fell off when I tripped on the pavement." The passerby joined the search but after 15 minutes, they had not found anything. "Where exactly did you trip?" he asked. " About a block up the street." "So why are you looking for it here?" " The light's better here the man replied.