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Case file

Dunning-Kruger Effect

Filed under
Need To Act Fast

The charge

People with low skill in a domain often overestimate their performance because they lack the knowledge needed to spot their own mistakes.


How it operates

The skills required to perform well often overlap with the skills required to evaluate performance, so weak performers can also be weak self-assessors.

Logged incidents

  1. Incident 01

    A novice PM declares strong product judgment after one successful launch and ignores missed assumptions.

  2. Incident 02

    A junior analyst trusts a fragile model because they cannot see its statistical flaws.

  3. Incident 03

    A new manager is sure their one-on-ones are excellent despite poor team feedback.

What to watch for

Watch for very high self-ratings paired with little objective evidence or weak error detection. Ask: 'What expert review or hard test would likely show I am wrong?'

Recommended action

Use external feedback, deliberate practice, and calibration against objective criteria rather than self-evaluation alone.

Known associates

Source of record

en.wikipedia.org

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