Accountancy firms have generated considerable media attention in recent years due to a lack of substantiated audits. This study found that only a third of 252 auditors provide a substantiated assessment for a representative task. Those auditors who performed well indicated that they encountered critical situations in the past and gained experiences from which they drew important lessons. By making mistakes discussable, by providing feedback and by encouraging self-reflection, accountancy firms can make a significant contribution to the quality of their auditors’ judgments.