At Spartez Software, we’ve found that when we’re planning the next sprint, going through all the stories in detail during the planning meeting doesn't make sense—it simply leads to an ineffective meeting. This is especially true in Scrum teams of 5 or more people who can complete a significant number of stories in one sprint. The reasons for this differ across teams, but the main one is that with big sprint backlogs, people find it hard to keep the purpose and details of each story fresh in their minds. Another reason is that stories are not usually refined enough to mean the same thing to everyone. Such situations can easily lead to a meeting taken up by explaining basic facts about each story to the team. Nobody wants that.
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