Because we lack the conventional metrics to define and measure, for example, the hardships of walking, we don’t design and enforce solutions or adopt targeted public policies.
Designers in almost all fields make critical decisions based on their domain knowledge, observable conditions, and of course data. More and more, incredible amounts of finely grained and immediately available (and updated) data is required to be incorporated into product decisions. Given the quantitative nature of some of this data, it is often judged to be unbiased, truthful, and complete. Few people take the time to question the data - not the accuracy per se, but what is (and is not) being measured.
This article highlights the assumptions and challenges urban planners encounter when considering the health of our cities. It also shows how qualitative data can be used to make clear problems that purely quantitative approaches often fail at capturing. Indeed, its hard to imagine the level of instrumentation required to provide the nuance captured in a stroll down a city street.