Process Improvement Methodologies---Organizations should decide

Very often, people tend to ask “which is the best improvement methodology to adopt?’

Though my bet lies with Lean, but I would say “it actually depends on what exactly does your organization need”. People are usually confused about the most spoken and used improvement methodologies – Lean, Six Sigma and Theory of Constraints (TOC).

I recently read an article which very interestingly differentiate the three as shown below:

Process Improvement Methodologies	Focus	Result
Six Sigma	focus on reducing variation and  achieving uniform process results in less waste, less throughput time and less inventory	If we focus on reducing variation,   then we will have more uniform process output.
Lean	focus on waste and flow time results in less variation, uniform output and less inventory	If we focus on waste removal, then flow time will improve.
TOC	focus on constraints and increased throughput results in less inventory and a different accounting system	If we focus on constraints, then throughput volume will improve.