Lean and Six Sigma: Best Friends or Worst Enemies
I recently spoke with Gary Jing, Site Quality Manager at a major manufacturing facility, about Lean, Six Sigma, whether one is better than the other, when to use one vs the other, and more.
Gary leads over 40 quality professionals across three plants and has spent years as one of the first master black belts at Seagate. His take? There’s a time and place for both, sometimes individually, sometimes at the same time.
In this post, I’ll share the practical framework Gary uses to get the most out of both approaches.
We surveyed 1,000 manufacturing professionals to better understand how quality is perceived. See the results in our research report: Are Leaders and Frontline Teams Aligned?
Why Organizations Create False Competition
Lean and Six Sigma are often seen as competing methods, which leads to confusion on the shop floor. In practice, they solve different problems and can support each other. The real challenge is understanding which one fits the situation.
The Execution-Level Friction
At the ground level, teams argue about fundamentally different approaches. “Six Sigma emphasizes data collection, data utilization, and analysis. Lean talks about focus on efficiency,” Gary told me.
Six Sigma practitioners want lots of data – even if it’s not immediately useful – because digging into it later can reveal hidden patterns. Lean practitioners view this as waste that slows processes and adds no immediate value. Teams spend energy debating methodology instead of solving problems.
Executive vs. Ground-Level Perspectives
While teams argue on the shop floor, executives don’t see a conflict at all. Gary once asked Jack Welch – former GE CEO and godfather of Six Sigma – about reports claiming Welch regretted not introducing Lean first.
Welch’s response: “If you do them well, you get the same thing.”
What executives understand is that both methodologies serve the same goal: better operations and improved results. Tactical differences become irrelevant when you focus on outcomes instead of methods.
Understanding the Complementary Nature
The reality is that Lean and Six Sigma aren’t competing approaches – they’re two lenses focused on the same problems. “Lean is typically from the angle of waste and flow, and Six Sigma is from the angle of defect or variation,” Gary explained.
They Really Do Match Up
“One thing I personally want to highlight is that they actually match up – defect is one form of waste and variation interrupts flow,” Gary added.
This isn’t just theoretical alignment. When you eliminate waste through Lean activities, you often reduce variation. When you control variation through Six Sigma tools, you typically eliminate waste as well.
Why Integration Matters More Today
This alignment is critical in modern manufacturing.today’s manufacturers face constant change, including new technologies, evolving customer expectations, and supply chain disruptions.
That kind of complexity demands quick adaptation and solid analysis. You need Lean’s speed and flexibility, plus Six Sigma’s problem-solving muscle.
“The synergy between the two outweighs those friction points,” Gary emphasized. Each methodology strengthens the other when applied strategically rather than competitively.
The One-Two Punch Implementation Strategy
Gary’s approach to combining Lean and Six Sigma isn’t just theoretical – it’s a practical framework he has used across multiple manufacturing environments. He calls it the “one-two punch,” and it solves the methodology debate by showing teams when to use which approach.
However, here’s the critical part: setting realistic expectations from the start prevents the disappointment that often kills improvement programs.
Start with Lean for Quick Wins
“Lean is more of a grassroots type of common-sense type of practice. So it’s suitable for all levels of people, employees, and so forth,” Gary told me. This makes Lean the natural starting point.
Getting started with Lean doesn’t require extensive training or advanced analytics skills. Teams can spot obvious waste, improve flow, and achieve quick results without getting bogged down in complex tools.
Follow with Six Sigma for Deeper Analysis
Once you’ve addressed obvious problems through Lean activities, you might hit a wall. The remaining issues require data analysis and statistical tools – exactly what Six Sigma provides. When you eliminate waste through Lean activities, you often reduce variation. When you control variation through Six Sigma tools, you typically eliminate waste as well.
As Gary put it , using the 80/20 rule: “80% of the problem can be addressed by 20% of the tools.” You don’t need master black belts to get started – Yellow Belt and Green Belt levels deliver strong ROI without huge barriers to entry.
This sequence eliminates methodology friction because teams understand why they’re using different approaches at different times.
Expanding Beyond Traditional Quality Thinking
“In general, manufacturing may hold a little bit narrow view on quality, right? But in a broad sense, quality probably should refer to producing a product that constantly meets customers’ expectations and also the specs. […] Because those are more objective and agreeable in a way,” Gary told me. This creates a dangerous blind spot.
Focusing only on specs creates a dangerous blind spot. If they don’t capture what really matters to customers and stakeholders, you’ll end up solving the wrong problems.
Building Integrated Quality Systems
The solution is expanding your definition of quality beyond specifications. “Even though we may stay with the terminology’ voice of customer, the meaning is really voice of stakeholder,” Gary explained.
When you apply both Lean and Six Sigma with this stakeholder mindset, you start addressing real-world problems that impact your entire operation, not just what looks good on paper.
The Bottom Line
The one-two punch approach Gary outlined isn’t complicated. Start with Lean to grab the obvious wins and build momentum. Once you’ve addressed the straightforward issues, utilize Six Sigma tools to delve further into the remaining problems.
What makes this work is realizing both approaches share the same goal: better operations and stronger results.
The manufacturers who get this right build sustainable competitive advantages by using the right tool for each situation, not debating which methodology is superior.
Ready to hear more insights from Gary about combining methodologies, setting realistic expectations, and building improvement capabilities that actually stick? Listen to the full episode here.
