Sydney Opera House: The Planning Fallacy

When the Sydney Opera House broke ground in 1959, it was billed at four years and about 7 million Australian dollars. It opened in 1973, having cost roughly 102 million. The estimates weren't reckless on paper, the design won an international competition under a respected architect, but the curved shell proved nearly impossible to engineer, construction methods had to be invented mid-build, and delays, redesigns, and a change of architects compounded on each other into a textbook cascade.

For founders and operators, this is the planning fallacy named by Kahneman and Tversky: the systematic, experience-proof tendency to underestimate how long things take and how much they cost. The case sharpens a decision you make every quarter, how to set a timeline and budget you'll actually hit, and why your own detailed plan is exactly the wrong thing to anchor on. The corrective move, the shift in where you look before you commit, is the lesson the app makes you arrive at instead of stating it for you.