Lean sigma is an innovative fusion of two process disciplines that have revolutionized modern business - lean production and Six Sigma continuous improvement.
We all know the inimitable power of Six Sigma - its rigorous process methodology, the disciplined thinking that focusing on root causes brings, and of course its tangible results. The structured DMAIC process (Define, Measure, Analyze, Improve, Control) is second to none for reducing process variation and eliminating defects. Yet few can deny that Six Sigma projects sometimes lack awareness of a vital third dimension - time. This is where lean thinking can add huge value, through a focus on total flow efficiency and minimizing overall process time.
Lean manufacturing was the real "machine that changed the world" as described in the classic study by Womack, Jones & Roos. The aim of lean production is to totally eliminate waste, or "muda", which can arise in seven forms - correction, overproduction of inventory, transportation, movement, waiting, overproduction and processing time. Authors such as Eli Goldratt with his ground-breaking "theory of constraints" advocated producing just up the level of a bottleneck to minimize inventory, and only then working to remove or "elevate" the constraint. It is just this kind of systemic thinking that Six Sigma needs to support its rigorous data focus.
Early on during Six Sigma training we learn about tackling the "hidden factory", which represents the sheer dead weight of re-work and re-engineering that results from defective process performance. Six Sigma continuous improvement is the ideal weapon to tackle the "cost of poor quality" but still needs lean sigma thinking to optimize flow throughout the entire value chain of the business. For example, strategic decisions such as co-locating supplier parks with assembly plants can add immense value. Just-in-time manufacturing success stories are built on these kind of value chain decisions, yet these would rarely fall within the finely focused scope of a classic Black Belt project. Lean thinking provides a much needed dose of the flow and the strategic into Six Sigma. It not only asks the question "How can we make this an effective, world class process" but adds, "In a lean system, do we need this process at all?"
So we can expect to hear much more of lean sigma,the perfect alliance between flow and precision. This marriage of the two most powerful quality management techniques in the world today will surely deliver impressive results. Kaizen, or continuous improvement, can be achieved through rigorous process analysis at the micro and the macro level. Lean sigma training will energise Yellow Belts, Green Belts, and all those that feel disillusioned by decades of disjointed quality initiatives. The market for lean sigma certification is likely to grow exponentially, and I note that TBM Consulting has registered the elided version of the name and the domain. We can only wish them and all other quality practitioners the best of luck as they develop this powerful business strategy.
Lean sigma thinking can perhaps finally move us beyond blind data worship and a step closer to Deming's original vision. True change is inner and cultural, and every time I rejoice in a data-driven, quantitatively robust project I remember the cautionary, inspirational words of Deming's 14 Points. "Eliminate slogans, exhortations and targets for the workforce asking for zero defects and new levels of productivity...Eliminate quotas. Substitute leadership".
The holy grail of perfect quality remains elusive, but lean sigma is one step further on the quest.
(c) James Rozel 2010
