In 2016, I interviewed an entrepreneur named Sean who had co-founded a small technology startup based in London. As with many organizations at that time, Sean and his team relied on e-mail as their primary collaboration tool. “We used to have our Gmail constantly opened,” he said. Then they heard about a slick new instant-messenger service named Slack that promised to streamline office communication: “There was this hype, so we decided to try it.” Once the team switched to the tool, the rate of back-and-forth messaging intensified, eventually reaching a stressful peak when a demanding client insisted on the ability to directly communicate with Sean’s employees using Slack. The team soon burned out, and two engineers quit. In desperation, Sean moved the company off Slack. When I spoke with him, some time had passed since this incident, but the memory of the service’s omnipresent notification ping remained strong. “I hear that sound, it gives me the shivers,” he said.