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Case file

Planning Fallacy

Filed under
Not Enough Meaning

The charge

Planning fallacy is underestimating how long, costly, and messy future tasks will be even when similar tasks ran over before.


How it operates

The inside view focuses on the current plan and misses common delays, coordination costs, and hidden work.

Logged incidents

  1. Incident 01

    A migration slated for two sprints takes four months.

  2. Incident 02

    A renovation budget doubles after work starts.

  3. Incident 03

    A board commits to a launch date before dependency mapping.

What to watch for

Ask: What happened on the last few projects of this type?

Recommended action

Use reference class forecasting and a premortem before setting commitments.

Known associates

Source of record

en.wikipedia.org

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