From my own experience, where Scrum has broken down is the promise of, after the sprint, you have something you can "release".
Of course, the term "release" can mean many things to many people. If you're building something substantial, an initial sprint or two may be dedicated to simply getting some overall framework in place. It just depends on what you call "release".
In the cases where I've seen failure, "release" could mean only one thing -- a shipping product outside the organization to customers. In spite of declarations from the dev team that no product going to customers would be delivered. And, at the end of a sprint, with no product prepared to go to customers, product management decided scrum was a failure. I'm not making this up.
Of course, the term "release" can mean many things to many people. If you're building something substantial, an initial sprint or two may be dedicated to simply getting some overall framework in place. It just depends on what you call "release".
In the cases where I've seen failure, "release" could mean only one thing -- a shipping product outside the organization to customers. In spite of declarations from the dev team that no product going to customers would be delivered. And, at the end of a sprint, with no product prepared to go to customers, product management decided scrum was a failure. I'm not making this up.