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The planning fallacy is that you make a plan, which is usually a best-case scenario. Then you assume that the outcome will follow your plan, even when you should know better.

"The Truth About How We Think". Interview with Jennifer Robison, www.gallup.com. March 20, 2012.
The planning fallacy is that you make a plan, which is usually a best-case scenario. Then you assume that the outcome will follow your plan, even when you should know better.