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Case file

Pseudocertainty Effect

Filed under
Need To Act Fast

The charge

In multi-stage decisions, we overweight options that remove uncertainty at one stage even when total odds are no better.


How it operates

Local certainty is psychologically attractive, and people often fail to multiply probabilities across stages.

Logged incidents

  1. Incident 01

    Leadership chooses a vendor that guarantees phase-one approval even though overall project success is lower.

  2. Incident 02

    A PM prefers a launch plan with a 'certain' pilot win but worse end-to-end conversion.

  3. Incident 03

    An M&A team picks a deal structure that secures one milestone while worsening total expected outcome.

What to watch for

It shows up when a guaranteed step feels more important than total success. Ask: 'Have I looked at the whole probability tree, not just one branch?'

Recommended action

Draw the full decision tree and calculate cumulative probabilities and expected value.

Known associates

Source of record

en.wikipedia.org

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