One of the most absurd ideas in politics is that everything is either left or right. You are either a liberal or a conservative. The reason why this is absurd is because there are many different political systems that can be used and within a government there are many different policies that can be implemented. Politics is complex, and left versus right oversimplifies.
For example, I once spoke to someone and told him that one simple way that the government can raise more revenue is to increase taxes and then all of a sudden this person called me a “liberal” and then started criticizing me for supporting abortion. I make one comment about taxation and then suddenly my views on everything else is known. I am pro-abortion, for gay rights, etc.
This is very similar to racism. Racists will assume, for instance, that just because someone’s skin is black that he is a criminal when logically this is false. Not all black people are criminals. Likewise, just because someone wants to increases taxation, it doesn’t mean they are pro-abortion. In fact, what does taxation have to do with abortion?
This is what is wrong with left versus right. The views lumped together on the left have nothing to do with each other. Just because someone is pro-abortion, why would that mean he is pro-taxation? Just because someone is anti-taxation, why would that mean he is anti-military?
There is absolutely no logic to the political spectrum, but I suspect many people love it because it fulfills the human need to belong to groups.