Whether a person is an archer shooting with a bow and arrow, or a hunter, soldier or policeman shooting with a gun, they will need some light if they want to shoot their weapon accurately at a target. If it is completely dark, the shooter will have to guess where the target is and likely miss it.

If the shooter is extremely lucky, the target might get hit just by chance. That is why, when we don't know the answer to a question or inquiry and we have to guess, we can say. "I'm going to take a shot in the dark." If we could see the answer clearly, we would feel more confident. If we guess at it like "a shot in the dark," however, we would be extremely lucky to get the right answer.