If you assume that most post travels between points that are close to one another, putting the most specific modifier first makes sense. Most of the time you on

If you assume that most post travels between points that are close to one another, putting the most specific modifier first makes sense. Most of the time you only have to think about a small part of the address to route correctly. That breaks down if the assumption is incorrect, and also to some extent if you have many different places with the same name that all receive lots of mail from you. So you're essentially right: It's an artifact of how the postal system used to work. Though both assumptions still apply more often than you might think.