I give CSM trainings with Jeff Sutherland, and about half a year ago he had put something in his material called "the dynamic model of Scrum". The essential feature was the addition of a READY state opposite the DONE state. The idea here is that a team needs to be in a stable, known situation to be able to perform well. It immediately struck a chord with me: I had seen so many teams thrash because the Product Owner could not give them a clear objective, the READY state was exactly the goal to work to. But what was it really, and how do you get there? By now I think I've got some good answers to these questions.
Here's a picture from my Scrum course material to illustrate the concept...
What does the READY state do?
In a self-organizing team setting a clear destination it very important: self-organization does not exist if you have nothing to organize TO. The READY state prevents team thrashing by ensuring that the preconditions for a good Sprint execution have been met. More ...
For a description of how to systematically quadruple velocity of a Scrum team by focusing on ready and done states see:
C. Jakobsen and J. Sutherland, "Scrum and CMMI – Going from Good to Great: are you ready-ready to be done-done?," in Agile 2009, Chicago, 2009.
English 
French 
Spanish 
English