Not just intellectual endeavours, the planning fallacy shows up everywhere. I have a book called Industrial Megaprojects by Murrow[0] which gives a lot of exam

Not just intellectual endeavours, the planning fallacy shows up everywhere. I have a book called Industrial Megaprojects by Murrow[0] which gives a lot of examples of financially disastrous multi-billion dollar projects. His conclusion? It's not really the doing of the project that was wrong, it was that the projects shouldn't have been done in the first place. The estimates and preliminary investigations were underdeveloped and this typically leads to overoptimism. Bent Flyvbjerg has also done a lot of work on megaprojects[1] and his basic conclusion is that well-estimated projects don't get built, because almost no megaproject is ever viable or cost-effective in itself. So there's a survivor bias towards "bad" projects, ones that are poorly planned in the first instance, magnifying the effect. In terms of software, agile/lean has the advantage of limiting commitment. It's easier to terminate something that's cost very little and not gotten far than to terminate something that's several years and millions of dollars into going nowhere. The former can be dismaying and annoying. But by the time serious time and money have been spent, there's a sunk-cost fallacy and often, personal pride or status of powerful individuals is involved. [0] https://onlinelibrary.wiley.com/doi/book/10.1002/9781119201045 https://onlinelibrary.wiley.com/doi/book/10.1002/97811192010... [1] https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2424835 https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2424835