Megaprojects 1: Why do 99% of them fail?

What is a megaproject? And why do they so often fail to deliver their promised benefits on time and on budget. From the Pyramids to the Parthenon, and from Willie Brown's Transbay Terminal to Intel 'fabs' and Heathrow Terminal 5, our experts from VISION and Relevate unravel the mysteries. Featuring Billy Glennon, Connor Butler and Charles Spinosa, interviewed by Fraser Allen.