Larry Page's Comeback (2014)
In my time at Google I never understood on what criteria young PMs were hired.  The company would regularly reject engineering candidates who had very successful solo projects because they didn't correctly answer the generic Comp Sci and how-do-you-scale-search questions, but at the same time the vast majority of PMs I encountered were just a year or two out of undergrad, and had never built a product, never launched a product, never demonstrated any aptitude for connecting with users.  They were certainly personable, and overall were good communicators, but not --as a rule-- inventive or imaginative.