A project team realizes that an important task on the iteration backlog will take more time than originally estimated What should the project team do?

A core principle of agile development, particularly in Scrum, is the use of fixed-length iterations (time-boxing). If a task is larger than estimated and cannot be completed within the iteration without jeopardizing the sprint goal or the time-box, it should not be continued indefinitely. The team should raise this issue, typically during a daily stand-up. After discussing with the Product Owner, the appropriate action is often to stop work on the item and move it back to the product backlog for re-estimation and re-prioritization in a future iteration.

A. Continuing to work breaks the time-box, a fundamental rule of iterations/sprints, which disrupts the project's rhythm and predictability.
B. Removing a team member is a punitive and counterproductive action that damages team morale and psychological safety.
C. Adding resources mid-sprint often disrupts the team and can slow down progress further, as described by Brooks's Law.

1. Project Management Institute & Agile Alliance. (2017). Agile Practice Guide. Project Management Institute. Section 5.2.5, p. 51. "The team may not be able to get all the work they planned for the timebox, but they can get the work that they did finish to a done state."

2. Schwaber, K., & Sutherland, J. (2020). The 2020 Scrum Guide. Scrum.org. p. 9. "Sprints are fixed length events... No changes are made that would endanger the Sprint Goal."