Another way to think of points is to realize that we mostly use them in order to get the right number of Stories into a Sprint.
Each team is going to assign Story Points uniquely. It’s a language that the team develops.
When we’re a new team, we have no idea how many Stories/Points we can complete in a sprint. We might as well just take a guess at what seems right.
After about 3 sprints, most teams start to understand their own language of Points, and they have a baseline for average points per Sprint.
Normally, that baseline slowly increases over the first dozen sprints while the team learns how to work together. Eventually, the team has its own, well understood, velocity and can do a pretty good job of estimating how many stories will be completed in the next sprint.