Planning fallacy

What it is

Underestimating the time, cost and risk of our own plans while knowing similar plans overran, because we picture the best case.

Related

• Overconfidence effect bias
  The planning fallacy is overconfidence applied to our own schedules and budgets.
• Optimism bias bias
  Expecting things to go well makes plans too rosy.
• Exponential growth bias bias
  Both are errors about how fast things build: compounding in one case, accumulating delays and costs in the other.
• Forecast illusion bias
  A forecast about our own project is the planning fallacy.
• Strategic misrepresentation bias
  Underestimates can be honest (the planning fallacy) or intentional (strategic misrepresentation).

Appears in

• The 99 thinking errors in Rolf Dobelli's The Art of Thinking Clearly#91: Planning fallacy
• Kahneman and Tversky's heuristics and biases#10: The planning fallacy

References

• Wikipedia: Planning fallacy en.wikipedia.org
• The 99 thinking errors in Rolf Dobelli's The Art of Thinking Clearly en.wikipedia.org
• Kahneman and Tversky's heuristics and biases en.wikipedia.org
• Wikipedia: List of cognitive biases en.wikipedia.org
• Wikipedia: Cognitive bias codex en.wikipedia.org

More in “Deciding and acting: incentives, loss and commitment”