Closing the Lean Improvement Cycle

Continuous improvement is at the heart of Lean thinking. Improvements should be built into future efforts and measured for their effectiveness.

For our value stream to have this approach, it must view its efforts in terms of a cycle of learning. The most popular model of this cycle is the Lean Improvement Cycle or PDCA cycle.

This cycle was associated with W. Edwards Deming, who called it the Shewhart cycle after Walter Shewhart. This cycle is illustrated in the following diagram:

Figure 9.2 – PDCA cycle

As shown in the preceding diagram, the cycle has four phases of activities:

1. Plan: Determine what iterative step to take. This may be a step in a backlog that is ranked high in priority. Formulate the hypothesis of what outcomes may happen if this step is implemented.
2. Do: Add the step to your value stream’s workflow.
3. Check: Examine (or keep examining) the metrics you measure for your...