Why Doesn’t Unity Include a Built-in Player Movement Script?

It makes no sense at all that there is no built-in player movement script in Unity. Considering the fact that the player movement aspect is something that every game tends to have, it should not be that difficult to implement such a system. It could be advantageous to do this. The scripts would be useful when first person or third person movement is required, for example. Why hasn’t this been done? What are the reason’s this is the case? I think a discussion on this subject would benefit the community.