The Product Backlog, the Product Goal and Refinement

The Product Backlog is an emergent, ordered list of what is needed to improve the product. It is the single source of work undertaken by the Scrum Team. Product Backlog items that can be Done by the Scrum Team within one Sprint are deemed ready for selection in a Sprint Planning event; they usually acquire this degree of transparency through refining activities.

Product Backlog refinement is the act of breaking down and further defining Product Backlog items into smaller, more precise items. It is an ongoing activity to add details such as a description, order and size; the attributes often vary with the domain of work. The Developers who will be doing the work are responsible for the sizing. The Product Owner may influence the Developers by helping them understand and select trade-offs. Refinement is not a separate Scrum event and has no fixed timebox.

The commitment for the Product Backlog is the Product Goal. It describes a future state of the product, which can serve as a target for the Scrum Team to plan against. The Product Goal is in the Product Backlog; the rest of the Product Backlog emerges to define what will fulfill it. A product is a vehicle to deliver value — it has a clear boundary, known stakeholders and well-defined users or customers, and it could be a service, a physical product or something more abstract. The Product Goal is the long-term objective for the Scrum Team: they must fulfill (or abandon) one objective before taking on the next.

Study focus: there is one Product Backlog per product, even with several teams, and one Product Owner who orders it. "Definition of Ready" is a complementary practice some teams use; it is not part of Scrum.