Halfway through a Sprint the Developers accept that they will not finish most of the items they selected — the work was much larger than they thought. They ask the Product Owner to cancel the Sprint so they can start again with a realistic plan. Is that a proper use of cancellation?

Professional Scrum Master I, objective 1. Understanding and applying the Scrum framework medium

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The options

Correct No — a Sprint is cancelled when the Sprint Goal becomes obsolete, not when a forecast turns out to be optimistic

Correct. The remedy here is the ordinary one: the Developers adapt the Sprint Backlog and, if the Sprint Goal is threatened, renegotiate scope with the Product Owner. The Sprint runs to its end either way.

Not correct Yes — a plan that cannot be delivered makes the rest of the Sprint pointless

Wrong, and it treats the plan as the Sprint. The Sprint exists to pursue the Sprint Goal; the selected items are a forecast, and discovering that a forecast was wrong is the system working rather than failing.

Not correct Yes, provided the Scrum Master agrees that the Sprint is unsalvageable

Wrong on both counts. It is not a cancellation reason, and the Scrum Master has no authority to cancel a Sprint even when it is.

Not correct No — a Sprint may never be cancelled once it has started

Wrong in the other direction. Cancellation is real and available; it is simply reserved for an obsolete Sprint Goal and reserved to the Product Owner.

Why

The distinction the exam tests is between a Sprint Goal that has become pointless and a plan that has become wrong. Only the first is a cancellation. The second is handled inside the Sprint, every Sprint, by the mechanisms Scrum already provides: adapt the Sprint Backlog, renegotiate scope with the Product Owner, and let unfinished items return to the Product Backlog when the Sprint ends on time.

Where this comes from

Cited
Scrum Guide section The Sprint
What it says
A Sprint could be cancelled if the Sprint Goal becomes obsolete.

Practise this

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Practise Professional Scrum Master I

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