Not quite correct. It predicted the end of a long cycle. I think the better question is why pay attention to what the Mayans had to say on the nature of the universe? They also believed human sacrifice was required to appease angry gods and weren't able to develop soil preservation and other agricultural management systems that would have kept their society from total collapse.

Fine, it predicted nothing about the end of the world, which is what this whole thing is all about. A "cycle" of what? Certainly not the apocalypse. The Mayan civilization was depraved and failed in a number of ways, hardly the kind of group I would lend much credence to.