How come politics always devolves into left vs right?

It has been like that across time and also between pretty much all countries that are not one party dictatorships.

Strange no? Politics seems to always be centralists competing with each other for their flavor of centralism. Classical liberals, libertarians and liberally (as in freedom) minded anarchists can't pull voters because the message of self reliance is a hard sale. The masses will vote for handouts because they're high time preference retards.