Gilligan explained that the reason Walt placed his watch (the one Jesse gave him for his 51st birthday) on top of the payphone after pretending to be the New York Times reporter was only retrofitted symbolism: The reason he had to do it was because they realized that in the flash-forward of him at Denny's that they'd shot for episode 501, Walt wasn't wearing a watch, so they had to explain where it went for continuity reasons. And so, out of necessity, they came up with what Gilligan called the "artsy fartsy" reason: It was a symbol of Walt, seeing the end is near, cutting ties with one of his "arch-nemeses," Jesse.