The incorrect statement is B, because auditors are permitted to adjust the audit plan based on materiality considerations identified during the stage 2 audit. ISO 19011 explicitly allows auditors to adapt audit plans as new information emerges, provided such changes are justified and documented. Preventing adjustments would contradict the principles of risk-based and evidence-based auditing.
Materiality is evaluated throughout the audit lifecycle. During initial contact and audit planning, inherent risks and organizational complexity influence audit duration and resource allocation, making statement A correct. During stage 1 audits, auditors review documentation and high-level processes to identify key areas that warrant deeper examination during stage 2, making statement C correct.
Statement B incorrectly suggests that once stage 2 begins, the audit plan is fixed and cannot be adjusted. In practice, if auditors discover that certain processes or assets are more material than initially assessed, they may legitimately reallocate audit time or adjust focus to ensure sufficient coverage of high-impact areas. This flexibility is essential to achieve reasonable assurance.
Therefore, statement B is not correct, as it contradicts established auditing norms and ISO guidance on audit adaptability.
