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At the base (but not the basement) of most process improvement programs, you'll usually find a set of recommendations or requirements that focus on measurement, analysis, and improvement. CMMI and Six Sigma have them as well.
These activities are important because they provide you with the empirical data and objective insight to assess your program and make it better. The measurements show you how you are doing. The analyses help clarify how you might do things better. And the improvements are your actions in response to the data.