This is 10 Questions, a new column in which we ask tech authors to pull back the covers on their recently released books. Interviews have been edited and condensed for clarity.

Zappos CEO Tony Hsieh was widely regarded by his tech peers and employees as a fun-first visionary. It’s why he located his company’s headquarters in Las Vegas, why the Zappos office had a petting zoo and a bowling alley, and why he assigned some employees the title of “fungineer.” But Hsieh’s quest for joy at work hid something far darker in his personal life. In their new book, “Happy at Any Cost: The Revolutionary Vision and Fatal Quest of Zappos CEO Tony Hsieh,” Wall Street Journal reporters Kirsten Grind and Katherine Sayre tell the full story of Hsieh’s life and the shocking circumstances of his death at age 46. Along the way, they probe bigger questions about work culture and mental health. “Why couldn’t someone of this stature, of this wealth get help? What exactly happened?” asks Sayre. “And what about our society—what about tech culture—set him up for a downfall?”

When and how did the idea for the book arise?

Tony Hsieh died suddenly after being locked inside a shed that mysteriously caught fire. As reporters for The Wall Street Journal, we were called in to figure out what had happened. We soon learned that Tony struggled with mental health and addiction, and he was left vulnerable to a cultlike group of people around him. We decided Tony’s story deserved to be uncovered in full detail.

Was there a singular experience that drove you to write it?

Tony spent the last year of his life in Park City, Utah, at a mansion known as “the Ranch.” We got photos showing every wall of the house lined with colorful Post-it notes. On each square, Tony and his entourage had scribbled everything from ideas about world peace and creativity to multimillion-dollar contracts for real estate. We wanted to know more about this bizarre enclave Tony had built.