Lean and Six Sigma are both methods of improving business productivity and performance and both systems have the same overall goal- to eliminate waste and create the most efficient running processes possible. The essential difference between Lean and Six Sigma is that each method defines the term ‘waste’ differently. There are many differences of opinion on which method is most effective but to determine this you must first understand the differences between each practice.
Six Sigma was first designed to be used within the manufacturing industries as a way to streamline processes to improve the quality and efficiency of a business’ output. However, after becoming widely used across manufacturing sectors it was quickly recognised as a viable way of eliminating waste from the processes of a variety of businesses.
Six Sigma uses two different sets of methodologies to examine aspects of a business and its processes, known as DMAIC (Define, Measure, Analyse, Improve, Control) and DMADV (Define, Measure, Analyse, Design, Verify)The DMAIC method is most applicable to the manufacturing and production processes of a company whilst the DMADV method works best when improving the customer relations of a business.
Six Sigma aims to improve a company’s running processes by working to reduce the number of errors during a production cycle. It does this by determining the root of any errors through examining data obtained by varying inputs.
The main focus of Lean is to cut out unnecessary steps that do not add value to the business, the way these wasteful steps are determined is by considering whether a customer would pay for this part of the process or not. Lean emphasises speed above all else during processes by looking at ways to reduce the amount of time between activities, events and cycles with the reasoning that the shorter the cycle, the more times it can be completed within a given time frame.
Lean and Six Sigma are often used in combination to examine and refine the running and production processes of a business. It is important to ensure that processes are completed without using unnecessary time, yet these processes must also be error free in order to avoid creating wasted products or services.