Chief Product Owner
... you have a Product Owner Team, and you need a single point of accountability for value.
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Development teams cannot collectively be held accountable for ROI. You need a single point of accountability for success and failure: not in a committee, but in a person: the "single wrenchable neck."
Have A Chief Product Owner who is the "single wrenchable neck" for the ROI owing to the product backlog of a Product Owner Team.
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The Chief Product Owner has a team of Product Owners working on pieces of the global Product Backlog. If there are multiple products, the Chief Product Owner has to manage a portfolio of backlog items and prioritize across products for each sprint or each release. The Chief Product Owner has a team of Product Owners working on pieces of the global product backlog. The Product Team needs to prioritize across the portfolio of Product Backlog pieces for each sprint.
Deming notes that quality decreases after a certain critical mass of inspectors is met: they defer to each others' judgment instead of feeling responsible. Sometimes, one head is better than two.