Of all the roles in a software or product development organization, I will argue the Product Manager’s (or Owner’s) job is the most challenging. On the one hand, the task of figuring out just what to build is complex and multifaceted. On the other hand, in any reasonably mature product organization, there is so much work that is going on and so much new demand, that the Product Manager can wish all they want in terms of product innovation and focus on the product roadmap, but failure and customer demand pretty much hijacks most of the Dev capacity in the organization.