Estimates are made by the people doing the work, which in Scrum means the Developers. Scrum does not require story points, relative units or any specific estimation technique.
Exam Question
A Product Owner wants advice from the Scrum Master about estimating work in Scrum. What guidance should a Scrum Master give? (choose the best answer)
- A. Product Backlog items must be estimated in story points.
- B. Estimates must be in relative units.
- C. Estimates are made by the people doing the work.
- D. Estimates are made by the Product Owner, but are best checked with the Developers.
- E. Scrum forbids estimating.
Correct Answer
C. Estimates are made by the people doing the work.
Why This Is the Correct Answer
The Scrum Guide says that during refinement “the Developers who will be doing the work are responsible for the sizing,” and that “the Product Owner may influence the Developers by helping them understand and select trade-offs.” The people building the item understand its complexity best, so their sizing is the most useful. How they size it, whether with points, hours, t-shirt sizes or not at all, is left to the team.
Why the Other Options Are Wrong
A. Items must be estimated in story points. Story points are a popular complementary practice, but Scrum does not mention them.
B. Estimates must be in relative units. Relative estimation is common but not required. The Scrum Guide does not prescribe units.
D. The Product Owner estimates, then checks with the Developers. The Product Owner can clarify and discuss trade-offs, but sizing belongs to the Developers.
E. Scrum forbids estimating. Scrum expects Product Backlog items to have a size. It just does not dictate how you arrive at it.
Exam Tip
Any option containing “must” plus a specific technique (story points, velocity, burndown charts) is usually wrong, because the Scrum Guide avoids prescribing practices.
Key Takeaways
- The Developers size the work they will do.
- Scrum does not prescribe estimation units or techniques.
- The Product Owner influences sizing through trade-offs, not by estimating.
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