Management that employs scrum is like a coach at a rugby or soccer game. It does everything possible to make the team play its best. It watches the team, makes substitutions, gets water, shouts advice, and cares passionately about the team and the game. The project is constantly changing. The activities within the project are constantly changing. Management watches while the game evolves and tries to help, but the game is in the team’s hands (or feet).
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Scrum demands the liberal application of common sense. If the date can’t be met, reduce the functionality that will be delivered. If the functionality can’t be reduced, reduce some of the capabilities within the functionality. Increase the cost by adding another team that Sprints in parallel, or bring in experts. Scrum will put all of the information that is needed to makes these decisions at Management’s fingertips. Management then has to decide how to maximise business value from the project.
From Agile Software Development with Scrum - Ken Schwaber.