Internal and external auditors independently verify that Controls are actually operating as intended, rather than just existing on paper. Internal audit typically reports to the Senior management / Board of Directors; external auditors are independent third parties, sometimes mandated by regulation (e.g. FINMA-recognised audit firms for regulated financial institutions).

Findings from an audit often surface previously unknown Vulnerabilitys or expired s that were never revisited, which is why regular audit cycles are themselves considered good practice on top of ongoing control monitoring.