User blog comment:Mrsupersauce/Cleaning up the wiki/@comment-189012-20120422132703

This is because we do not know whether the author might be coming back to write on this site. Every user has their own moment of hiatus, so you can't rely on this argument of "the author no longer uses the site."

The only way you can delete one's article is if that article broke the site's policies. To clarify on this point, this means that the author received a warning about his article breaking the policies and not fixing it. On this point, it should be noted that new policies cannot be applied to articles that received warnings for not complying the old policies. This would be unfair to authors who may return back to the site.