Один из самых известных экспертов по User Experience описывает преимущества use cases перед user stories.
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User stories and backlog items don’t give the project team any sense of “completeness” – what I keep finding is that the development team bids/estimates the projects at (e.g.) 270 story points, and then as soon as they start working, that number keeps increasing, seemingly without bound. The developers are depressed and the sponsors are equally depressed by this. How big is this project, really?