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Planning fallacy 0:54
A 54-second explainer of Planning fallacy, narrated over the same demo you can try yourself.
Try the interactive Planning fallacy demo
What this video covers
The planning fallacy is our habit of underestimating how long things will take and how much they'll cost, even when we know similar tasks have run over before. We picture the smooth, best-case version and quietly leave out the interruptions, rework and surprises that always show up - so the plan is optimistic almost by default.
Your gut estimate was the smooth run - everything going right, nothing interrupting. Reality added the bits you mentally skipped: the wait, the rework, the surprise. That gap is the planning fallacy, and it barely shrinks even when you know about it. The cure isn't trying harder to imagine the steps; it's anchoring on how long this kind of thing has actually taken before.
