#1 Luck

To win a Clasico, luck is always necessary. Always. No matter how many claim that footballing ability is what derives the outcome of a game, luck always plays at least a small role in deciding the outcome of a fixture of such high magnitude.
On a good day, Benzema’s header might have found the inside of the far post and have bounced into the net. On a good day, Cristiano Ronaldo might have shot the ball with his left and blasted the net with the raw power of his shot.
On a good day, Real Madrid might have been awarded a penalty for a handball inside the box. But it was just not a good day for the Blancos—which has been the case for quite a while in the league this season.
It is harsh to claim that luck allowed Barcelona to win as they really played well in the second half, but it can’t be denied that the god of luck wasn’t in favour of Zidane’s men.