Name authority files are often national in scope and will be created under different policy regimes. This is the rationale for VIAF (the Virtual International Authority File).
The Deutsche Nationalbibliothek, the Library of Congress, the Bibliothèque nationale de France, and OCLC are jointly conducting a project to match and link the authority records for personal names in the retrospective personal name authority files of the Deutsche Nationalbibliothek (dnb), the Library of Congress (LC), and the Bibliothèque nationale de France (BnF). [Virtual International Authority File [OCLC - Projects]]
Longer term, the future of authority control is interesting. Typically, the files will contain names associated with materials catalogued. Now, this is much better than not having any files, however, this will increasingly seem like a rather arbitrary slice of names. Think of what is not included: people who have only published in articles or people who have only deposited stuff in archives, for example. And think about the national slicing, which presents matching issues as we begin to move data around much more.