One vision dominating much of urban planning worldwide is that of the 'smart city', whereby urban areas are pre-planned and designed to be managed via digital technology with efficiency prioritised as the top objective. But planners cannot foresee how cities will need to develop depending on cultural trends, changes in economic sectors, and other factors. We lose something important if we over-plan and over-manage our cities. The concept of the city as a pre-engineered machine works against critically important quality-of-life considerations. Once basic services, like transport, are in place, urban dwellers value community cohesion, opportunities for self-expression, and other quality-of-life features as much as or even more than efficiency. Such elements require openness, freedom of choice, and the opposite of central control in order to blossom.