The document discusses the crucial role of project managers in assessing and challenging business cases to prevent project failure, emphasizing that a project can be deemed unsuccessful if it lacks proper justification, regardless of whether it meets budget and schedule requirements. It highlights that common pitfalls in business cases arise from a focus on technical solutions rather than on achieving business objectives, and stresses the importance of maintaining a clear view of strategic value throughout the project. Ultimately, it argues for a shift in responsibility where project managers should actively engage with and critique business cases to ensure accountability and success.