The article looks at how being overly optimistic can affect the success of World Bank projects. They studied over 2,800 projects from 1960 to 2019 and found that about 60% of them were too optimistic. When projects were overly optimistic, they were less likely to succeed. The researchers suggest that it's important to accept uncertainty and complexity when approving projects, focus more on making projects successful rather than just accurate estimates, shift resources from planning to implementation, and change how projects are supervised.