Or “Why don't we just say the Sprint Goals the list of stories that we commit to?”
Or “What is the difference between establishing the Sprint Goals and committing to a list of Stories?”
Or “What is the purpose of PI Objectives?”
Teams should establish Sprint (or Iteration) Goals during Sprint (or Iteration) Goals Planning. The purpose of Sprint (or Iteration) goals is to:
Note that a lot of the discussion here is also related to PI Objectives. In many ways PI Objectives are like “Uber-Sprint (or Iteration) goals” in that teams development for an entire Program Increment length of time rather than just a Sprint (or Iteration). Reading below if you see “Sprint (or Iteration) goals” you can substitute “PI Objectives” and for “stories” read “features”.
The idea that a Sprint (or Iteration) Goals “provides flexibility” is often a stumbling block for new teams. Many teams do not differentiate between the user stories they are committing to in a Sprint, and the Sprint (or Iteration) Goals. The Sprint (or Iteration) Goals should not just be a restatement of the user stories. Often it is a summary of the stories, combining a few together, but that is a side result, not the purpose of the goals.
One of the main ideas behind having Sprint (or Iteration) Goals is that it gives the team a degree of flexibility on how they meet those goals. For example, if the team finds that a user story they have in the Sprint does not make sense because of something they have learned, then the team can make adjustments (delete user stories, make new stories) and still meet the Sprint (or Iteration) Goal. Can anyone say “decentralized decision making?”
One question that is often asked is “why don't we just say its the list of stories that we commit to”. There are a couple of problems with this approach:
The goals can also include other things such as “improvements” the team is expecting to do. For example, you’ll often see things like “develop initial working agreements” or “learn how to work as a team in agile” in the first Sprint (or Iteration).
As a final note, especially with respect to the improvement goals. You'll want to be clear about “how you will know you have achieved these goals”. For example, what does it mean to “learn how to work as an agile team” in this first Sprint. Perhaps the measure is “team thinks we are better prepared for the next Sprint” or some such and before your Sprint (or Iteration) Demo you have a quick survey (Fist of Five vote?) to validate, but you want to be able to say “we’ve met this goal” in some way.
Specifically on goals:
Related to the idea of goals: