You are not just a photojournalist, you're a historian.
There in front of me was the Senator on the floor being held by the busboy. There was nobody else around, and I made my first frame, and I forgot to focus the camera. The second frame was a little more in focus... then just for a second, while everything was open, the busboy looked up, and he had this look in his eye. I made that picture, and then suddenly the whole situation closed in again. And it became bedlam.(On the 1968 shooting of U.S. presidential candidate Bobby Kennedy.)
I think what makes a picture is a moment that is completely spontaneous and natural and unaffected by the photographer.
Reporters listen, photographers look. If you are doing your job seriously as a photojournalist, your sight must be the primary sense that you use at all times.