Business loves catchphrases and labels. That especially applies to improvement methodologies. So many refer to these methodologies as Six Sigma, when in fact, Six Sigma is actually a methodology of improvement. However, when you understand improvement methodologies, you will find that there are three different and unique improvement methodologies, only one of which is Six Sigma. The challenge in selection is to use whatever methodology that helps your organization improve. Let’s define three methodologies to help with this understanding:
Six Sigma – A focus on reducing variation and achieving uniform process, resulting in less waste, less throughput waste and less inventory.
Lean – A focus on waste and flow time results in less variation, uniform output and less inventory.
Theory of Constraints (TOC) – A focus on constraints and increased throughput results in less inventory.
Although the belief is there is commonality with the methodologies, the fact is they are distinct processes that achieve unique results through their application. It is important to understand the methodology and which theory will be accepted in the individual corporate culture. Change is embraced when acceptance is reached.
The first step in this process is to identify the primary theory that works best for your business and the one that will be quickly accepted within the culture. First we need to understand the primary theory of the methodology, then understand the primary theory of the tools and methodology. This is considered to be the “primary effect.” It is an if/then relationship. For example:
Six Sigma – If you focus on reducing variation, then you will have a more uniform process.
Lean – If you focus on waste removal, then flow time will improve.
TOC – If you focus on constraints, then throughput volume will improve.
It may appear that each methodology is driven towards common tools and concepts. However, the reality is that each methodology begins their journey from different perspectives, crossing commonality in the middle and ending with different results.
Deciding which methodology will work best for your organization begins with understanding the organizational culture and values. If your organization values analytical studies and data, then Six Sigma may be the best fit. If your organization values immediate change with visual results, then Lean may be the best choice. If your organization values a systematic approach, where process ‘buy-in’ is not crucial and you value separation of worker and management, TOC would be your choice.
Ultimately, there are many factors involved in choosing a methodology, but these core considerations should be your driving focus. Each methodology contributes valuable concepts, ideas and techniques. You must decide which will best benefit your organization.