We removed Zero Defect Mindset from MSF v4.0 because we thought it led to undesirable behavior. Bob Lews articulates the reasons well in this article about confidence versus commitment [registration required.] We had taken a very Edwards Deming approach to explaining why - that zero defects was "conformance to plan" and caused a focus on heroic effort to meet commitments that did not encourage continuous improvement while the alternative of "reduction of variation" produced a focus on capability and provided a framework to drive continuous improvement. Bob puts it better and in lay terms.

He gets in to a deeper explation over at Advice Line and cites Robert Austin and Jim Collins as good sources of evidence for the idea that zero defects and accoutability as conformance to plan are not good ideas. Seems Bob appreciates the idea of management science for software engineering too. Technorati Tags: MSF, David+Anderson, Bob+Lewis, Deming, Robert+Austin, Jim+Collins, Zero+Defects