The Main Effect Leaders Should Really Be Watching
In continuous improvement circles, we spend a time talking about data — main effects, interaction effects, root causes, process behavior charts, and all the rest. But sometimes the most powerful “main effect” in an organization has nothing to do with statistical output.
It has to do with leadership behavior.
In the Cox-B0x cartoon above, I share how a team member proudly remembers learning what a main effect is… but applies it in a way that many organizations unintentionally reinforce:
“Everyone comes to see when you shut down production after making the change.”
It’s funny — but it’s true.
Too often, the biggest observable “effect” of a leader-approved improvement is the chaos it triggers afterward. Not because the idea was wrong, but because the system wasn’t ready and the leadership approach wasn’t aligned.
Leaders Don’t Just Approve Change — They Enable It
Whether you’re running a Green Belt project or a full-scale transformation, your leadership presence determines whether change becomes sustainable improvement or short-term disruption.
Here are three leadership reflections inspired by the cartoon:
You can find more in my book. Click here to download the first chapter:
Cultivating Champions of CI ~ SAMPLE ~ Chapter One
1. A Leader’s Job Isn’t to Celebrate Ideas — It’s to Prepare the System
Many leaders enthusiastically endorse improvements. Far fewer take the time to:
- Verify the process is stable before changing it
- Ensure the operators understand the “why,” not just the “what”
- Confirm support functions (maintenance, IT, quality, supply chain) are ready
- Remove roadblocks before the change goes live
If the system can’t absorb the improvement, the “main effect” everyone sees won’t be the benefits — it’ll be the fallout.
2. Leaders Are Responsible for Psychological Safety During Change
People watch leaders closely during improvement efforts. They notice:
- What you question
- What you ignore
- How you react when the results aren’t immediate
- Whether you blame people or investigate the process
In environments where people fear consequences, every adjustment feels risky.
In environments where leaders coach instead of judge, improvement feels natural.
3. The Real Main Effect Is Trust
Statistical “main effects” show which factors drive variation in a process.
Leadership main effects show which behaviors drive variation in culture.
When leaders:
- Communicate openly
- Support experimentation
- Stay present during transitions
- Model the behaviors they expect
…trust increases, performance stabilizes, and improvements stick.
Leadership Isn’t a Step in DMAIC — It’s the Multiplier
Tools matter. Data matters. Training matters.
But leadership behaviors determine what happens after the charts are printed and the meetings end.
The cartoon exaggerates the moment for humor, but it captures an uncomfortable truth:
People judge improvements not by the idea, but by the leadership around the idea.
When leaders create clarity, safety, and support, the “main effect” is unmistakable:
People improve processes because they want to — not because they’re told to.
What do you think? Ever experience the Main Effects of poor leadership? – Let me know in the comments.