If you think using AI means doing less at work, think again.
In a new eight-month study of how generative AI changed work habits at a US-based tech company with about 200 employees, researchers at the University of California, Berkeley Haas School of Business found that employees' work intensified in three main ways.
Employees multitasked more, took on a broader range of responsibilities, and worked longer hours, often without being asked to do so.
Aruna Ranganathan, a professor in management at UC Berkeley, and Xingqi Maggie Ye, a Ph.D. student at the Haas School of Business, detailed their research in a Harvard Business Review story, writing that once AI tools became available, workers began to usurp each other's roles, feed information to AI during meetings, and correct each other's vibe coding projects.
Ranganathan and Ye said that workers "described this as 'just trying things' with the AI, but these experiments accumulated into a meaningful widening of job scope. In fact, workers increasingly absorbed work that might previously have justified additional help or head count."
"Once the excitement of experimenting fades, workers can find that their workload has quietly grown and feel stretched from juggling everything that's suddenly on their plate. That workload creep can in turn lead to cognitive fatigue, burnout, and weakened decision-making," they wrote. "The productivity surge enjoyed at the beginning can give way to lower quality work, turnover, and other problems."
The researchers wrote that many workers also send prompts to AI before leaving their desk for a meeting or for lunch break, so AI could continue to work without supervision.
"These actions rarely felt like doing more work, yet over time they produced a workday with fewer natural pauses and a more continuous involvement with work," Ranganathan and Ye added.
In an October 2025 interview with Rowan Cheung, who hosts the Rowan's Notes interview series, Sam Altman, the OpenAI CEO, also shared ways in which AI may have made his work more intense.
"It's almost like, I don't think I can come up with ideas fast enough anymore," Altman told Cheung.
"I really do have a hard time trying to reason through exactly what this is going to mean," Altman added. "I think it will mean that stuff just happens faster and that you can try a lot more stuff and figure out the better ideas quickly."
