- releases can help answer this question.
- Dependencies: Weather we like it or not, dependencies in the product backlog are a fact. Functional requirements, for instance, often depend on other functional and even nonfunctional requirements. And if several teams work together, dependencies between them can influence the prioritization. Dependencies that cannot be removed restrict the freedom to prioritize the product backlog and influence the effort estimates; the item on which others depend has to be implemented first.
Prioritization is imperative as it directs the team’s work by focusing the team on the most important items. It also freezes the backlog contents progressively – items in the product backlog are detailed according to their priority.
The Grooming Steps
To ensure that the product backlog is DEEP, we have to regularly groom it. Grooming the product backlog is an ongoing process that comprises the four steps listed below. These are not necessarily carried out in the order stated:
- New items are discovered and described, and existing ones are changed or removed as appropriate. A great technique to capture functional requirements on the product backlog is user stories. User stories describe functionality form a user’s perspective, are easy to use and can be smoothly refined incrementally.
- The product backlog is prioritized. The most important items are now found at the top. The lower-priority items are found at the bottom. It’s clear which items will participate in the next release or product version and in which order the items will be implemented.
- The high-priority items are prepared for the upcoming sprint planning meeting; they are decomposed and refined until they are ready: The are clear – the entire Scrum team has a common understanding of the items. They are feasible – small enough to fit into the next sprint so they can be transformed into a product increment according to the definition of done. And they are testable – they can be validated so that the product owner can assess if an item was successfully implemented or not at the end of the sprint.
- The team sizes product backlog items. Adding new items to the product backlog, changing existing ones, and correcting estimates make sizing necessary. Common measures of size are story points and ideal days. A great technique to facilitate team estimations is planning poker. Note that team members don’t estimate the work individually. The team agrees on the likely team effort.
Grooming is Teamwork
Although the product owner is responsible for making sure that the product backlog is in good shape, grooming is teamwork in Scrum. Items are discovered and described, prioritized, decomposed, and refined by the entire Scrum team – Scrum allocates up to 10% of the team’s availability for grooming activities (Schwaber 2007). Stakeholders are also involved as appropriate. Grooming the product backlog collaboratively creates a dialogue within the Scrum team and between the team and the stakeholders. It removes the divide between “the business” and “the techies.” It eliminates wasteful handoffs, and avoids miscommunication and misalignment. Requirements are no longer handed off to the team; the team members coauthor them. This increases the clarity of the requirements, leverages the Scrum team’s collective knowledge and creativity, and creates buy-in and joint ownership.
Some teams like to do a bit of grooming after their Daily Scrum. Others prefer weekly grooming sessions or a longer grooming workshop toward the end of the sprint. Grooming activities also take place in the sprint review meeting when the Scrum team and the stakeholders discuss the way forward; new backlog items are identified and old ones are removed.
My favorite tool to support product backlog grooming