“There’s another one!” Cameron Burke’s son said, pointing to a darkened streetlight across the park. “But it’s out too!” Cameron regretted having started this game with his four-year-old. His company, Lumiscape, produced smart, connected streetlights that had been installed in cities throughout the United States, including Cleveland, where they were now, visiting his parents. He and Graham had decided to squeeze in a walk to Forest Hill Park before bedtime, and he’d challenged the boy to count all the lights he could find. But they’d already seen three that weren’t working properly.

A version of this article appeared in the July–August 2016 issue (p.119–124) of Harvard Business Review.