ummm... the first macintosh operating system had neither a documents folder nor an applications folder. There was no logical place to store any applications or user data. In OS 9, it's still screwed up, because some apps won't install into the applications folder even though you specifically tell the installer to do it! If only apple would link the /Documents folder to the first user's ~/Documents folder, and tell the finder to open to the home directory when making a new window, it would be much easer on the user.
What Panther Should Fix: Part Four, Duplicate Directories