6.3. Why do some items reappear when I run PrivacyScan?

OS X automatically creates new "default" files for some items when they are cleaned from the system, including Finder Recent Items, Safari Cookies, etc. These newly created files are simply empty or template files used by the operating system to store data going forward. This is normal behavior for the operating system, and does not indicate any problems in cleaning the files.

If PrivacyScan is unable to clean a file, it will let you know, as seen here.