These are the most widely cited reasons for audits and a having a formal audit program . I do find interesting the word practical in the second bulleted list item. Think subjectivity.
Why A Formal Audit Program?
To ensure the documented systems meet specified requirements.
To ensure the documented systems are practical, understood, and followed throughout the business.
To maintain records of audit activity including areas audited, nonconformances, and corrective and preventive actions.
ISO 19011 - Quality and Environmental Management Systems Auditing Forum Discussions
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