Why do they give you an appointment when they aren...

Why do they give you an appointment when they aren't able to receive you at the appointed time? I have been waiting for an hour and still no door. Why do they overbook appointments. There are a lot of truck's still checking in. Poor effing management!!!! I was hoping to get back to the house for the weekend but that is not going to happen after setting around here waiting on these incompetent DA's.