At the end of a Sprint, a Product Backlog item worked on during the Sprint...

According to the Scrum Guide, if a Product Backlog item does not meet the Definition of Done, it should not be included in the Increment for the Sprint1. The item is considered unfinished and therefore cannot be part of the Increment that may be released or presented as ‘Done’. The undone work should be re-estimated and put back on the Product Backlog for the Product Owner to prioritize for future Sprints2. This ensures transparency and maintains the integrity of the Increment’s quality.

References: The Scrum Guide provides clear guidance on handling undone work and emphasizes the importance of the Definition of Done as a quality standard for the Increment1. The Professional Scrum Product Owner™ (PSPO I) materials also align with this approach, underscoring the Product Owner’s role in managing the Product Backlog and ensuring that only ‘Done’ items are considered for release