Lean Six Sigma: How to Combine Lean and Six Sigma for Maximum Impact

What Is Lean Six Sigma?

Key Terms

Lean Six Sigma

A process improvement methodology that integrates the waste-elimination philosophy of Lean Manufacturing (derived from the Toyota Production System) with the statistical defect-reduction rigour of Six Sigma (developed at Motorola). Together, they address both speed (Lean) and quality (Six Sigma) simultaneously, producing faster, more reliable processes at lower cost.

Explore the Full Lean and Continuous Improvement Toolkit

• ►Lean Manufacturing: Definition and 5 Principles
• ►Plan Do Check Act: The Improvement Cycle
• ►The 7 Wastes: Identifying and Eliminating Muda
• ►TQM Tools: Quality Management Toolkit

The following section contains our original guide.

Lean Six Sigma is one of the latest trends for continuous improvement.

Its aim is to combine both lean principles with six sigma, in one framework.

It makes sense:

Lean and six Sigma both share the goal of improving processes.

So, when you’re improving your own processes, why not combine the two tools to get the best of both worlds?

What’s Lean Six Sigma All About?

Lean focuses on speed and agility.

By optimising processes, you can improve productivity and throughput. By reducing waste, you can improve lead times.

I’ve seen first hand, the power of lean. In one instance I facilitated a project where we improved a 6 month lead time for a company’s major product, down to 4 weeks.

That’s eliminating a whole 5 months of customer waiting time. All from a lean initiative.

If done right, you can expect massive gains when optimising processes through lean.

Six Sigma’s Focus is Slightly Different

On the other side of the spectrum is Six Sigma.

Six Sigma focuses on eliminating variation from a process.

Let’s say that your customer feedback scores varies drastically from 1 through to 10. They are so inconsistent that you find it hard to put a mark in the sand of what to expect from your customers.

This inconsistency is where Six Sigma can shine.  Where a process is not stable, you can use Six Sigma to improve it and provide consistency.

If you just focus on improving efficiency.

But don’t look at quality…

You could be making product faster and throwing it away, quicker.

On the contrary, if you improve your quality to a consistent defect free level… but not making it quick enough, you’re not going to satisfy the customer with meeting their demands.

In a Nutshell, think of lean six sigma as the following deadly duo:

• ►Improve efficiency and productivity (Speed) – Lean will give you that…
• ►Improve quality and consistency – Six Sigma will do a great job here.

3.4 Defects per Million!

What is Lean Six Sigma? In it’s rawest form, Six sigma is built around the concept of building so much process precision, that actual results from that process will only create on average, 3.4 defects per million opportunities. That is, if your process repeated 1 million times, and with a Six Sigma capable process, it would only produce 3.4 defects!

That’s pretty accurate and precise.

Having a six sigma process means you can set it and forget it.

No more firefighting.

No more time and money consumed inspecting the process to death.

Lean Six Sigma Tackles the 7 Process Wastes

There’s more on the 7 wastes in my other guide. But lean six sigma directly tries to eliminate common process wastes.

They are seen in summary below:

Transportation

Inventory

Movement

Waiting

Over processing

Overstocking

Defects

And it does it through a structured step-by-step process called DMAIC.

DMAIC is simply a 5 step methodology that ensures you tackle improvements in the right way and with the right level of detail.

Here’s a summary of DMAIC:

Define the problem

Measure the process or problem area

Analyse the data to understand what’s causing the problem

Improve the process or area by eliminating the factors which cause the problem

Control the process or improvements made, to ensure it doesn’t slip back

Lean Six Sigma is a powerful combination to help create competitive advantage!

How is a Successful Lean Six Sigma Approach Applied?

The most successful approaches have often started with the lean tools, first. This means making the workplace more efficient. This is done by mapping value streams, seeing the barriers to flow and then eliminating waste.

This method will optimise processes and improve process linkages.

Process linkages are critical, because when work or information is passed from one team to another, it often waits for that team to process that work.

By improving process linkage, you can reduce the waiting time and increase throughput and flow.

When process problems remain, its then time to look more in depth.

That’s where the switch to Six Sigma helps. Six Sigma uses more detailed statistical tools to help analyse and improve processes.

Lean Six Sigma Focus on the following sequence:

• ►Always focus on the customer and how you can add more value
• ►Map the value stream and see how the work gets completed.
• ►Eliminate waste to make the vale streams flow
• ►Use data to reduce variation and root causes.
• ►Use the people in the processes to drive improvements. Change can’t be done for people.
• ►Consistently improve in a systematic and structured way (Using DMAIC)

Don’t Forget People

What’s often forgotten is the cultural aspect.

It’s all very well improving processes, but changing behaviours is needed to maintain the process improvement.

And to ensure that everyone in the organisation can spot issues and use the appropriate tools to improve.

Focus should go into teaching people to use lean six sigma tools, to spot issues and improve them across the business. And at the lowest level of the organisation.