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Decision MakingMember ingredient
Planning Fallacy
People can underestimate their own task-completion time even when they know similar tasks have taken longer, but overruns can also come from changing scope, incentives and uncertainty.
Public evidence overview
One checked source, with its limits.
This preview is not the complete evidence base. Use it as a question to investigate in your own product, not as a prediction of what an individual will do.
Checked source previewAcademic paper
The Planning Fallacy
Research-assisted source review
- What it supports
- People can underestimate personal completion time despite knowing similar tasks run late; task unpacking, perspective and past-outcome prompts work inconsistently across conditions.
- Where it may not transfer
- A narrative programme review is not a preregistered meta-analysis. Much evidence comes from education and individual tasks and does not establish causes of organisational overruns.
See how sources and limitations are checked in our editorial method.
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