The Scrum Guide is a great, simple instruction book that reminds people how to get the best out of Scrum. Remember, the Official Scrum Guide (Sutherland and Schwaber, 2017) is only 13 pages long, so don’t over complicate things. As a framework, it is purposefully incomplete. You need to add to it in order to contextualise it to your own environment.
While it reads very black and white, knowing how to accomplish things like Backlog Refinement still remain a mystery to many.
As an agile coach, I like to keep things simple for new Scrum Teams. This includes Backlog Refinement sessions. Yin and Yang is one of my favourite patterns to teach new Scrum Teams how to collaborate on refining the Product Backlog together in a few short sessions.
Empiricism
While Backlog Refinement isn’t a compulsory event in Scrum, like Daily Scrum or Sprint Review, it supports empiricism by helping to make the work in the Product Backlog transparent.
What is the Yin and Yang Pattern?
The Yin and Yang pattern for Backlog Refinement creates a number of formal sessions for refining the Product Backlog.
Ying
- Scope boundaries are clarified for each addition to the Product Backlog.
- When work contains “unknowns”, assumptions are listed regarding what they “might be”.
- Assumptions and the confidence about those assumptions are listed.
- Risks are noted, including impact and likelihood.
- Any assumptions with less than an 80% confidence should then subject to further investigation.
- Investigations, experiments and research activities are outlined – ones that will directly improve the level of confidence about the assumptions listed. Each experiment is an hypothesis – that the actions presented and any associated plans will improve the level of confidence about an assumption. The outcome of the test of this hypothesis will be discussed at the “Yang” Backlog Refinement session.
- Timeboxes are set for every experiment, with an outcome to be reached for discussion at the “Yang” session.
- Product Backlog items are estimated and further detail is added to them that will assist their delivery by the Development Team.
- A time for the “Yang” session is agreed on – occurring before the end of the Sprint.
Yang
During this session, the Team:
- Discusses the experiments and investigations that were run.
- Discusses the findings from those activities.
- Related whether the confidence in the assumptions increased and its effects on the risk of likely failure of delivery should the Team commence delivery of the item next Sprint.
- Re-estimates the PBI based on the findings of the experiments, investigations and research.
Ultimately, the Yang session should assess the results of experiments, research and draft design activities and their improvement of the confidence of solutions just-in-time for the next Sprint.
Things to consider
- The more the Development Team uses its 10% of the Sprint length on Backlog Refinement the more prepared they’ll be for Sprint Planning. Sprint Planning should really be the last opportunity for talking about Stories.
- Don’t do Backlog Refinement on the last day of the Sprint. The Development Team tend to be running for the finish line and are busy getting stuff “Done”.
- Don’t spend the entire 10% timebox doing Backlog Refinement as a team. Spend a few short sessions together to plan who will attack what Stories and what they’ll do to pre-plan them so there won’t be any surprises or unknowns during delivery.
