For an action plan to be effective, it must address the root cause of an observation. The root cause is the underlying reason why a problem or issue has occurred. By targeting the root cause, the action plan can help prevent the recurrence of the issue and ensure long-term resolution. Addressing only the condition or the symptoms of the problem may lead to temporary fixes, whereas understanding and resolving the root cause leads to more sustainable improvements.References:
* Institute of Internal Auditors (IIA), Practice Guide - Root Cause Analysis.

Section: Volume B
Explanation/Reference:

Omitting advance client notice when planning an audit engagement is justifiable if the engagement includes audit assurance procedures that involve sensitive or restricted assets. Providing advance notice in such cases could compromise the integrity of the audit, as it may give management an opportunity to conceal or alter the status of these assets. The goal is to ensure that the auditors can observe the actual condition and handling of sensitive assets without any prior alteration. Reference: IIA Standard 2201 - Planning Considerations, IIA Practice Advisory 2201-1