However, the follow-up questions are critical to determine skill and luck. In the case of the bad trade, the self-awareness of what went wrong is critical. What specifically did the manager miss? Have the manager give the details and why it was missed. How is this missed information now being incorporated in the investment process? In the case of the good trade, what made the manager lucky? The good trade could have right for the wrong reasons. The direction could have been right but the magnitude of the impact could have been wrong.
The critical job of the due diligence analyst is to overcome the uncertainty from the Dunning-Kruger effect. This process is especially difficult in global macro trading and model building, so extra care should be taken with these manager reviews.