Too, how you view things now, this visit and then next visit can determine how well the meds might be working. Your whole life history kind of gives a picture of your life and it's hard to get to know and treat "you" without knowing that. A primary care physician wants to know all of your medical history, the story of your body; it makes sense that a psychiatrist would want to know the story of your mind, what/how you think, what has influenced you, etc.