I am working in a Scrum-team that has been developing software for the past year. The organisation isn't used to agile product development and initially provided a weak product owner who was chosen because of his functional knowledge about the domain, but since we're developing both a functional system and a new technical architecture, he recently quit this position because he couldn't find himself adding much value to the team.
Besides the Scrum-team (programmers and testers), there is a relatively new separate project leader/manager who is responsible for budget, a software architect approving technical decisions and a requirements engineer (currenly 'interim product owner') who sees himself as chicken helping out the hypothetical product owner. And then there is the test department and operations. These all are the stakeholders in this project and the organization has trouble appointing a product owner, because they 'can't find anybody who has enough knowledge and time to take on the job'.
Fortunately most of my colleagues are smart, pro-active people and we are constantly debating among ourselves to make the right decisions and I think we're doing quite well under the circumstances.
However, not having a product owner does slow us down and demoralizes the team in my opinion, because nobody seems to want to take responsibility for the final product except for the project leader/manager who only appears for demos, when approving timesheets and in weekly 1 hour meetings to inform the team about future organizational plans regarding this product, but also giving us a chance to speak up if there are any issues. A while back, I have asked the project manager to invest more time in making and maintaining a full release planning, so we can plan ahead and make choices about priorities accordingly. Although he response was positive, I have yet to see any results.
How would you proceed?