At least according to Tech Crunch it was because Ammann also failed to deliver something on Barra's agenda [1]: And while Ammann continued to push the company

At least according to Tech Crunch it was because Ammann also failed to deliver something on Barra's agenda [1]: And while Ammann continued to push the company to expand, there were missed targets, notably the plan to launch a commercial robotaxi business in 2019. The company has spent the past two years inching toward that commercialization goal, along with the rest of the industry, which has gone through a spate of consolidation. Most likely that's a lot harder to get done than anyone thinks. Is Vogt really the guy to make it happen? I guess we'll find out. But GM sending an otherwise successful VP packing after more than a decade there signals they are looking to shake things up. GM is not Silicon Valley and even senior execs IMHO enjoy longer tenures that you'd find in the Valley. They also skipped over the whole reassigning him to another role / oh he's left to pursue other interests tap dancing you often see to give people some runway or cover to leave. Not sure whether to read anything into that or if that's just how Barra operates. [1] https://techcrunch.com/2021/12/16/longtime-gm-exec-dan-ammann-is-out-as-cruise-ceo/ https://techcrunch.com/2021/12/16/longtime-gm-exec-dan-amman...