Hi there, as an ISO 9001 Internal Audit Trainer, I like to recommend my new participants start their first audits off with a seasoned auditor and audit in pairs. That way, the newly trained auditor can learn and be "calibrated" to the organization's audit style. Even after the new auditor is adjusted to the organization, it is always a good idea to assess the ongoing auditor performance. It's good to review the audit work documents including the quality of the reports prepared. Also, I like to take a peek at the type of issues raised in an audit. Is one auditor always raising inspection issues yet the others do not? Does one auditor always find training issues in each audit? Are the findings relevant to the scope of the audit? Ongoing calibration of auditors is important. Great question.