Why smart city megaprojects failed: Learning from the past and planning for the future

Smart city megaprojects routinely fall short of the utopian visions promoted by their creators, yet the failure of these projects has not been systematically compared across cases or grounded in a shared analytical framework. This paper addresses that gap by examining ten smart city new-town projects from around the world, including Songdo, NEOM, Sidewalk Toronto, Masdar City, and others, at various stages of development, construction, suspension, and abandonment. Drawing on literatures in high modernist planning, megaproject failure, splintering urbanism, and smart city critique, we develop a seven-dimensional evaluation framework organized into three reinforcing categories: conception and design (feasible, technological), governance and process (engageable, equitable), and viability and impact (financial, ecological, livable). Each case is scored on a four-point ordinal scale based on documentary evidence, enabling structured comparison across political systems, economic contexts, and geographic regions. Three findings stand out. First, engagement failures were the most universal dimension, present in all ten cases, regardless of regime type or project leadership. Second, technological failure was the least common, challenging the assumption that smart cities fail primarily because the technology does not work. Third, financial failure was present at the highest severity in every abandoned project, extending megaproject optimism bias theory to the smart city domain. The paper concludes with policy recommendations for incremental planning, early-stage participatory governance, equity-centered design, and independent regulatory oversight.