In the context of process improvement, Lean and Six Sigma are two methodologies that can work together, since they have some points in common.
It is important not to confuse these concepts or end up losing focus, by dividing the process improvement effort between Lean and Six Sigma, and end up not correctly executing either of the two approaches.
In this article, we will point out the main differences between Lean and Six Sigma, and then show what exactly these two ways of analyzing processes and promoting their improvement are based on.
Process Improvement with Lean and Six Sigma
Difference of approaches: less waste & more quality
These two methods of process improvement, Lean and Six Sigma, present a simple difference to understand and that is very important to consider when applying either of them.
It can even be said that despite this difference, the Lean and Six Sigma methodologies complement each other.
The aim of the Lean approach is to make processes lighter and more agile, reducing the interval between activities.
As the processes are followed in the production cycles, by decreasing the time between tasks, the cycles will be faster and will occur more times in the same time interval.
To achieve this, the Lean method aims to eliminate waste, which we will detail later.
The Six Sigma methodology aims to eliminate defects, with the aim of improving quality and better serve customers.
To achieve this, it has five stages, which we will also explain below.
The 7 wastes that should be avoided in a Lean process
By controlling each of these wastes, and trying to avoid them, the process will become increasingly light and agile.
- Defects: when a product or service does not meet the customer’s specifications, in addition to creating the loss of the customer, a waste will be created to try to repair this error or replace it.
- Downtime: when a task of the process is not done because the previous delivery (a resource, information, authorization or others) has not occurred, it is evident that it will result in delays and waste.
- Unused talent: a human resource that is not well used or that is not recognized is one of the most serious waste that can happen in a company.
- Transport: whenever it is possible to avoid transport, this should be done by installing stocks close to the production site or the end of the assembly line adjacent to the dispatch room, for example.
- Inventory: To have too many stocks, without necessity, is a total waste of resources that could be used in other activities, besides creating storage expenses, insurance, rent and others.
- Movements: the flow of information and resources must be optimized, which in addition to reducing risks, makes the operation more agile and even transparent, in some cases.
- Additional processing: if an electric cable is enough with a rubber cover of 1 millimeter for its use, producing it with more than that is an extra and unnecessary processing, characterizing it as a waste.
The 5 stages of Six Sigma (DMAIC cycle)
Reduce defects and ensure a high level of quality. Where to start?
The Six Sigma methodology begins by defining where the company needs to eliminate errors and defects, and then proceed with the other stages, see:
- Define: discover which processes of the company add more value to the productive chain and must present the best possible quality level.
- Measure: objectively and reliably measure the performance of these processes.
- Analyze: analyze the collected information to discover the origin – the causes of the nonconformities – to define where there are opportunities for improvement.
- Improve: correct and prevent defects by optimizing processes.
- Control: continually check if the improvements implemented are really bringing the desired effects and check for new optimization opportunities.
Undoubtedly, practicing the improvement of processes with Lean and Six Sigma used in a complementary way can bring quite satisfactory results.
And if you can count on a Business Process Management tool to design these processes with agility and precision, even better.
Find more information about Lean Six Sigma in this video: