what is required when a scrum team says a product backlog item is done?

Absolutely. In the context of scrum, saying a product backlog item is 'done' signifies that it has been completely developed, tested, and accepted by the product owner according to the definition of done set by the team. This definition often includes several activities and checks, like passing all necessary tests, meeting coding standards, and documentation.

Good question. Disagreement within the team can occur. That's why it's crucial to establish a clear and shared 'Definition of Done' at the beginning of a Scrum project. This document, typically created collaboratively by the scrum team, sets clear, objective criteria for when a task is considered finished. It helps reduce misunderstanding and disagreements, ensuring that everyone operates on the same page.

In cases where a backlog item does not meet the agreed 'Definition of Done', it cannot be considered 'done', and typically, it is moved back to the backlog for further work. It's important to remember that quality assurance is a key principle in Scrum. Any tasks not fully meeting the criteria should not be passed off as complete to maintain the integrity of the product.