HKSM
Non-Functional Requirements
Nonfunctional requirements are often incomplete early in a project. New quality attributes may emerge during Sprint Reviews or Retrospectives. When discovered, they should be captured and ordered in the prioritized product backlog.
Key Points
- Nonfunctional needs (e.g., performance, security, reliability, usability) may surface after work has begun.
- Identify them during Sprint Reviews or Retrospectives and turn them into backlog items.
- Define clear acceptance criteria and reflect them in the Definition of Done when appropriate.
- Estimate and prioritize alongside functional stories, as they can affect architecture and testing.
Example
In a Sprint Review, users report slow page loads. The team adds a backlog item: "As a user, I want product pages to load within 2 seconds under average load," defines acceptance criteria and test approach, estimates it, and reorders the backlog with the Product Owner.
PMP Example Question
During a Sprint Review, a stakeholder requests stricter security logging to meet compliance. What should the team do next?
- Add the work to the current Sprint without changing the backlog.
- Create a nonfunctional backlog item with acceptance criteria, estimate it, and reprioritize with the Product Owner.
- Wait for the next release planning meeting to consider it.
- Update the Definition of Done immediately and apply it to all in-progress work without adjustment.
Correct Answer: B — Add it to the prioritized product backlog with clear criteria and prioritization
Explanation: Newly discovered nonfunctional requirements should be captured as backlog items, estimated, and prioritized with the Product Owner rather than inserted mid-Sprint or deferred unnecessarily.
