"My portraits are more about me than they are about the people I photograph.” - Richard Avedon
A portrait tells two stories. First the obvious, it tells the story of the people in the photograph. Second, it tells the story of the person behind the camera. What a person chooses to photograph shows what they are interested in and what moments they find significant enough to freeze in time. You can learn a lot about there character, ie. whether they take serious portraits or funny ones, fabricated portraits or realistic ones, portraits of older people or of young kids, etc.