This podcast episode explores the concept of the planning fallacy, our tendency to underestimate the time, effort, and resources needed to complete a project, leading to cost overruns and schedule delays, particularly in infrastructure megaprojects. The discussion examines contributing factors such as mental simulations, optimism bias, and coordination neglect, while highlighting strategies to overcome this bias, including reference class forecasting, strategic misrepresentation, and the use of data and statistical models.