Crafting Effective User Stories: The Power of INVEST
In agile software development, user stories are essential for planning and execution. They serve as containers to express user needs clearly and concisely, enabling technical practitioners to build complete solutions. To write effective user stories, agile practitioners employ various techniques, including the INVEST principle. This set of guidelines helps evaluate a user story’s quality, ensuring it meets the necessary attributes.
Understanding User Story Attributes
When writing user stories, it’s crucial to consider the following attributes:
- Who it’s for: The target user for the user story, often expressed as a persona or user type.
- What it seeks to achieve: The goal(s) of the target user.
- Why it matters: The reason(s) those user goals are important.
- How to know it’s complete: The forms of evidence that show the user story has met expectations.
A popular way to write user stories is to use the following syntax: “As a [role/persona/user type], I want [goal or action] so that [desired result from goal/action].” This syntax helps teams address the who, what, and why aspects of user stories.
The INVEST Criteria
The INVEST principle, first articulated by Bill Wake in 2003, is an acronym that stands for:
- Independent: The user story is conceptually separate from other user stories and doesn’t rely on their completion.
- Negotiable: The story is an “invitation to a conversation,” allowing the team to evolve the story during discussion until a balanced solution is reached.
- Valuable: The completed story clearly meets an actual user need.
- Estimatable: The story is detailed enough for the team to estimate its relative size.
- Small: The story can be completed in a short time window without losing value.
- Testable: The story can be tested to ensure it passes a clear set of acceptance criteria.
Applying INVEST in Scrum
When planning, Scrum teams follow a predictable cadence. They refine user stories, choosing the ones to work on during the next sprint. By applying the INVEST criteria during backlog refinement and sprint planning, Scrum teams can realize benefits associated with each area of the INVEST principle.
Complementary Concepts
The INVEST principle aligns with other concepts, such as:
- The Three Cs: Card, Conversation, and Confirmation, which represent the initial concept, dialogue, and shared understanding of a user story.
- The DEEP principle: Detailed, Estimated, Emergent, and Prioritized, which applies to the product backlog as a whole.
Remembering Key Points
When using the INVEST criteria, keep in mind:
- You can’t remove all uncertainty; ongoing team communication is essential.
- Many attributes of user stories are subjective; involve multiple team members when writing and clarifying stories.
- Perfection is neither desirable nor possible; aim for “good enough” when articulating user stories.
By evaluating user stories against the INVEST criteria, you can improve team alignment and deliver software that customers love.