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Case file

Sunk Cost Fallacy

Filed under
Need To Act Fast
Also recorded as
Concorde fallacy

The charge

We continue a failing course of action because we have already invested time, money, or effort in it.


How it operates

Stopping makes past losses feel real, so persistence becomes a way to avoid that pain.

Logged incidents

  1. Incident 01

    A team keeps funding a feature with no adoption because six months were already spent.

  2. Incident 02

    A company renews a vendor because switching would 'waste' implementation costs.

  3. Incident 03

    An investor holds a thesis solely to get back to breakeven.

What to watch for

You may be in it when past spend is a main reason to continue. Ask: 'If I had not already paid for this, would I start it today?'

Recommended action

Use prospective framing and explicit kill criteria at stage gates.

Known associates

Source of record

en.wikipedia.org

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