In order to ensure that a specific file type is never moved down to a secondary file tier, the administrator should:

Periodically accessing a file may update its last-accessed timestamp but does not enforce a retention policy - the ARX could still migrate the file based on other configured criteria.

This is factually incorrect because ARX does support policy-based tiering controls that can explicitly prevent specific file types from being moved to secondary storage.

ARX's policy engine allows administrators to define rules based on file type, ensuring certain file types are always retained on primary storage and never demoted. When the policy is applied, the ARX enforces it for every matching file, overriding any default tiering behavior that would otherwise migrate the file to a secondary tier.

Placing files in a non-tiered directory requires manual end-user action and bypasses ARX's built-in policy engine, making it an unmanaged and unreliable workaround.