Meta’s most famous employee Yann LeCun breaks silence on why he left Mark Zuckerberg’s company

AI pioneer and Meta’s most famous employee Yann LeCun has opened up about his departure from Meta after more than a decade, revealing that mounting pressure from CEO Mark Zuckerberg and fundamental disagreements over the company’s AI direction ultimately drove him to leave. In an interview with the Financial Times, the 65-year-old computer scientist—who won the prestigious Turing Award in 2018—didn’t mince words about Meta’s pivot toward large language models and the hiring of 28-year-old Alexandr Wang to lead the company’s superintelligence efforts.

LeCun told FT that Zuckerberg “basically lost confidence” in Meta’s generative AI organization after the team “fudged” benchmark results for Llama 4, released in April 2025.