Hardcore tech execs are meeting their match: the limits of the human body

Lilian Weng, cofounder of Thinking Machines Lab, resigned on Monday citing health issues, becoming at least the fourth high-profile tech executive to step down for health reasons amid the AI arms race. Others include Fidji Simo, CEO of AGI at OpenAI; Greg Yang, cofounder of xAI; and Tom Siebel, CEO of C3 AI. Experts like Jan Gerber, CEO of a burnout recovery clinic in Zurich, and Dr. Judith Joseph, a New York City psychiatrist, warn that AI-driven demands for extreme productivity are exacerbating burnout and health problems among tech workers.

In tech's hardcore era, some execs are facing an obstacle they can't outsmart: the limits of their own bodies. On Monday, Lilian Weng, the cofounder https://www.businessinsider.com/thinking-machines-lab-cofounder-lilian-weng-steps-down-stress-illness-2026-7 of Thinking Machines Lab, became at least the fourth high-profile figure at tech's cutting edge to cite the state of her health in her resignation announcement. More later on the career change that became public shortly thereafter. Before Weng, Fidji Simo https://www.businessinsider.com/top-openai-executive-fidji-simo-is-stepping-down-2026-7 , the CEO of AGI at OpenAI, the xAI cofounder Greg Yang https://www.businessinsider.com/xai-cofounder-lyme-disease-advisory-founder-mode-greg-yang-2026-1 , and Tom Siebel https://www.businessinsider.com/vcs-almost-took-the-whole-system-down-billionaire-ceo-2023-3 , the CEO of C3 AI, all stepped down from their roles, saying they were too sick to work at the level of intensity they expected from themselves. Each situation is unique, and we can't know if work triggered the execs' health problems. But the pattern begs the question: Is the AI arms race moving too fast for its own creators? Chronic illness and relentless work: a match made in hell Various tech and business execs have made lofty predictions that AI will make us so productive that three- or four-day work weeks https://www.businessinsider.com/jpmorgan-ceo-jamie-dimon-ai-day-shorter-work-week-2023-10 could one day be the norm. Jan Gerber https://www.businessinsider.com/burnout-treatment-center-founder-ignored-symptoms-2025-12 , the CEO of a recovery clinic in Zurich for burned-out execs, told Business Insider he's seeing the opposite happen. "If you don't want to fall off the train, you need extreme focus, extreme hours, and constant networking just to keep up," he said of working in AI. Gerber shared an anecdote from a Silicon Valley founder: Although he uses AI agents to hash out million-dollar contracts that he signs off on, the time freed up is only stuffed with more work. "This doesn't mean more time for family, but more deals happening, more to keep an overview of," Gerber said. Svetlana Makarova, an AI product leader at the healthcare platform IKS Health who previously worked at the Mayo Clinic, told Business Insider's Thibault Spirlet in April https://www.businessinsider.com/ai-impact-on-jobs-rising-expectations-workers-2026-4 that human workers are beginning to face "unrealistic standards for productivity, patience, and availability. Unlike people, AI never has a bad day." That level of automation can come at the expense of human workers' creativity, which would otherwise boost well-being and ease stress, said Dr. Judith Joseph, a psychiatrist based in New York City whose employees work bi-coastally. "When workers sacrifice creativity and individualism in order to meet high demands to overperform and use automations, this may contribute to burnout," she said. Now more than ever, the tech industry is obsessed with speed and optimization, from workflows to blood sugar https://www.businessinsider.com/intermittent-fasting-benefits-and-risks-for-longevity-weight-loss-cancer-2024-4 . As Business Insider reported last year, the days of job security and lavish perks https://www.businessinsider.com/tech-industry-amazon-microsoft-meta-google-companies-intensity-hardcore-2025-3 have been replaced by the constant threat of layoffs and the intense pressure to dominate AI. Stress, of which there is plenty in Silicon Valley, is itself hard to deal with, and can trigger and worsen poor health. Long-term conditions that are physiologically distinct have a few things in common that are incompatible with hardcore work culture: mental and physical exhaustion, time away for health appointments, and for some, unpredictable flare-ups. "I've experienced firsthand how difficult healthcare can be to navigate, even when you have every possible advantage," Simo wrote in her statement. Hardcore industry, hardcore workers Then there's the brutal catch-22: Tech attracts folks with a consuming, all-or-nothing approach to work. "There's a degree of self-selection in who ends up running tech companies," Gerber said. Competition is intense as the industry faces a wave of consolidation "that will leave a small number of winners," he said, adding: "That 'eat or be eaten' dynamic pushes people to work even harder, ignore early warning signs, and keep pushing until they hit burnout." In her resignation notice, Weng said she considered taking a narrower role, but said, "that's not my personality. If I cannot give it 100% for what I should be responsible for, I fail my job." Simo wrote that she regretted not taking Mark Zuckerberg's advice when she worked at Facebook to take a year of medical leave. "Looking back, I realize that a lot of what made me successful also made this decision incredibly difficult," she said. There's also the matter that, partly thanks to AI, the tech industry has quickly gone from one with relative career stability to facing admittedly still unproven predictions of mass unemployment. "Other industries do not face this same drastic level of employee replacement threat," Joseph said. As Business Insider's Julia Herbst and Robert Scammell have reported, software engineers https://www.businessinsider.com/great-coding-reset-ai-software-engineering-2026-7 have borne the brunt of AI disruption so far. As the models and agents the industry worked so hard to create shift its working culture, some of its leaders are rethinking their long-term career strategies. Siebel of C3 AI, for one, returned https://finance.yahoo.com/markets/stocks/articles/thomas-siebel-back-c3-ai-132000808.html?guccounter=1&guce referrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNvbS8&guce referrer sig=AQAAAJ397VkVMcPVeIZZ8wuS9LOQeB3WHpg8tdbXk7W8a8hqe89hG qz72sh9CFk4LQcIW0huDeSw4tcPXzzm2yD0ttqNtzFvERXO2AAWVs7J9I0HlvNbIFv5np7tEBFI-8HZcvPT2v0usJiuJGSyjAN4xHVqwxoFjY7yB6d-rpDkXFw to the company as CEO shortly after leaving it. In her resignation notice on Monday, Weng wrote that she wanted to move out of the cofounder role, not the industry. On Wednesday, OpenAI said she would be rejoining the company — where she previously worked from 2018 to 2024 — in a research position https://www.businessinsider.com/lilian-weng-returns-to-openai-after-leaving-thinking-machines-lab-2026-7 . "Grit and endurance are not the only skills required to have impact over decades," Simo wrote. "Sometimes the harder thing is to stop, listen, and trust that taking care of yourself today makes it possible to contribute for much longer tomorrow."