INVEST checks before prioritising and sizing stories
Key Takeaway
Run the INVEST checks before you prioritize and size a story. Split a story that bundles work or overlaps another story, and estimate each story only closely enough to rank and schedule it.
INVEST is a checklist of six qualities that a good user story has: Independent, Negotiable, Valuable, Estimable, Small, and Testable. Check stories against it before backlog planning. The checks show which stories are ready to prioritize and size, and which ones probably need a rewrite first.
What a user story is
A user story is a simple description of a feature told from the user's point of view. Teams use user stories within the Agile methodology.
A story follows the format "As a <who>, I want <what> so that <why>." A story gives a synopsis of a requirement, not the full detail.
User stories save the team time when it prioritizes the development or implementation of requirements. They also avoid the restrictions that come from defining specification details too early.