Juan Manuel Marquez is facing Manny Pacquiao again for a very specific reason: He wants the definitive win, on the record books.
Juan Manuel Marquez: "The people say, why again? Why again, (fight) Pacquiao? I said because I want to prove who's better. I want the referee to raise my hand. ... I don't like the judges' decisions. I don't like it because everybody knows what happened the last three fights. I'm training very hard, and I'll see you on December 8."
That's a pretty straightforward statement as to why Pacquiao vs Marquez IV is happening, from Marquez's side: He wants to get that official win. I don't think there's any real doubt that this gnaws at him, and has for years. It gnawed at him after '04, after '08, and after last year. Marquez has a white whale. It's an official win over Manny Pacquiao.
No matter how much he tells himself or anyone else that he's won a fight, or two, or three, that's not what the history books say, and people look at record sheets. They don't read thoughtful articles and analyses of historical fights -- some people do, but you're the minority, and so am I. It says, for now, "Manny Pacquiao 2, Juan Manuel Marquez 0, Draw 1" to the majority out there.
He wants the win. I'm into that. I can go for that, Hall & Oates.