I've conducted many interviews with potential employees and candidates for special programs. Whiners and idiots get theirs wrapped up very quickly and quietly with a "Thanks for coming in, we will be interviewing candidates for the next few days, we should be making a decision early next week". Firing back at the emotionally stunted does nothing but feed whatever crybaby neurosis they are currently wearing on their sleeve and gives them more reason to whine and bitch (which is what they wanted to begin with).
No need to create drama when you can sweep it out the door. 
Question, sir, since you interview people.
Is it true that the longer the interview goes on, the more likely one's going to be hired?
I've found that true in my own life, but others say it isn't so.
But it seems to me if one's a loser, the interviewer would want to close things up as quickly as possible.