In reply to Jeff Chandler.

Aside from the ability to change the permalink, don't forget there is also another important use case of the Permalinks page.

Flush rewrite rules to debug issues caused by plugins that return 404 for certain pages / new post types. Sometimes this happen because there is a conflict between two plugins.

Usually an easy fix to that solution is: Go to your Permalinks page, don't change anything, and simply click on Save Permalinks.

This is huge help for beginners who don't want to flush rewrite rules by placing a code in their functions.php file.