> Grills, who is 33 and lives in San Francisco, typically works 10 hours a day and takes one weekend day off. She went through the Y Combinator startup accelerator program in 2024 and saw firsthand the effects of pushing too hard. A fellow founder in her cohort was hospitalized after failing to eat solid foods and living off mostly meal-replacement products. (Y Combinator says it has long advocated that its founders take care of themselves.)