"The Right" tends to be classified as such because they see value in preserving things that came before them. That there might be some merit to keeping things as they are and changing things slowly over time. Instead of focusing on how things should be changing, they focus on slowing down the process or even reversing it.

"The Left" focuses on pushing things in the direction they want, and will tear down anything in order to do so. And as they say, those who control the future control the past.