No changes are made that would endanger the Sprint Goal.

No changes to the team's implementation of the Scrum Framework, if doing so would endanger the Sprint Goal. For example no changes to team membership, development practices, or the Sprint Backlog should be allowed if those changes would put the achievement of the agreed goal in jeopardy.

Thank you.

But new PBIs can be added or removed, is that right?

Or can they only be added or removed if it doesn't impact the sprint goal?

The Sprint Backlog is a forecast of the work needed to meet the Sprint Goal. PBI's may therefore be added or removed from the Sprint Backlog in order to better achieve the agreed Goal.

Posted By Ian Mitchell on 01 Jan 2017 09:10 AM
The Sprint Backlog is a forecast of the work needed to meet the Sprint Goal. PBI's may therefore be added or removed from the Sprint Backlog in order to better achieve the agreed Goal.

I'm still confused about this. You're saying PBIs can be added or removed as long as the Sprint Goal isn't compromised but during the Management Plaza sample exam, I see this is the question and answer:



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Q: Who can replace Sprint Backlog items during the Sprint?
A: No one

Remember that there are two elements in the Sprint Backlog:

Items selected from the Product Backlog: we don’t change them after the Sprint Planning.
Tasks created by breaking down the items: they are always changing. Tasks are referred to as “work” in the PSM I exam and Scrum Guide.
The tasks (aka work defined in the Sprint Backlog) are changing all the time. However, the Scrum Guide is not clear about the items in the Sprint Backlog. Jeff Sutherland believes they shouldn’t change, and old writings from Ken Schwaber say that the items are frozen after the Sprint Planning. The only exception is that when you’re done with all items, you will pick the next item from the top of the Product Backlog.

The latest version of the Scrum Guide says that the Development Team can modify the Sprint Backlog as it learns more about the work needed to achieve the Sprint Goal.

Does the Guide make any exceptions to this, and say there are parts of the Sprint Backlog which cannot change?

I think it's all about the Sprint Goal and how to achieve it. If the team discovers after three days that it needs to create a particular middleware X, it can add a new estimated user story to the sprint [1]. Same with deletion of stories. Maybe after 5 days, they figure out that 3 tasks are not needed and user story Y is thus superfluous -> Team may drop the story.

What's *not* ok is if someone uses his or her influence on the team to get a story in the sprint that was not in planning and is not directed towards the Sprint Goal, because this would break the focus of the Sprint.

That's at least my take on it. Feel free to comment and challenge me.

[1] Short estimation of all team members. Important to get burn-down charts correct.