In this article we are going to look at Bill Smith, another Quality Improvement (QI) hero – and sometimes known as the ‘father of Six Sigma’. We’ll be finding out about the Six Sigma theory that he invented after having spent 35 years in quality assurance and engineering – a method that is widely used today within Quality Improvement.
Bill Smith, sometimes known as the ‘father of Six Sigma’ was born in Brooklyn, New York in 1929. After graduating from the U.S. Naval Academy in 1952, he studied at what is now known as the Carlson School of Management (formerly the University of Minnesota School of Management) and went on to work in engineering and quality assurance thereafter.
He spent some time in Japan and in 1987 he joined Motorola as vice president and senior quality assurance manager for the ‘Land Mobile’. There - along with his colleagues Mikel Harry and CEO Bob Galvin - he invented Six Sigma, which we will find out more about in this article!
When Bill Smith moved to Motorola in the 1980s, the company was intensifying its quality initiatives in order to try to catch up with Japanese competitors. Bill Smith had been brought into the company in order to share Japanese quality methods that he had learned while in the country with Motorola.
It was there that Bill Smith invented the Six Sigma improvement methodology - along with Mikel Harry - sharing the concept and theory with Motorola’s CEO and going on to develop it thereafter.
Let’s find out more about the Six Sigma improvement methodology. Bill Smith’s resounding belief was that in order to improve processes, you should involve people who are already doing the job.
“Six Sigma” was initially used to describe an ‘expected level of design margin and product quality’ and was presented as a ‘problem solving’ approach which had four stages, as follows:
It was this approach – also known as MAIC, which led to Bill Smith and his colleague Harry Mikal to develop the cornerstone of the Six Sigma process, later called DMAIC, which we’ll read more about later on in the article.
Six Sigma was designed in order to help organisations to improve processes: ‘This increase in performance and decrease in process variation helps lead to defect reduction and improvement in profits, employee morale, and quality of products or services.’
Six Sigma is also very much a customer-focused process, and the thinking that influenced it can be traced back as far as the 1920s, when Walter A. Shewhart derived his theory on three sigma. In fact, the core of Six Sigma can be described thus: ‘A product is built in the shortest time and at the lowest cost if no mistake is made in the process; and if no defect can be found anywhere in the process of building a product for the customer, then the customer probably will not find one either.’
The key principles of Six Sigma that were identified by Bill Smith are:
You can break down and apply the Six Sigma principles above to these two methodologies: Six Sigma DMAIC and Six Sigma DMADV. We mentioned DMAIC earlier - define, measure, analyse, improve, control – and this method is applied to processes already in existence.
While DMADV stands for:
The DMADV methodology is used to create a new process.
While Six Sigma has a focus on improving process control while reducing process variation – ‘lean’ promotes flow and drives out waste. You may sometimes hear the term ‘lean Six Sigma’ which is a blurring of the two methodologies – using elements of both theories to achieve positive results.
'Lean Six Sigma is a fact-based, data-driven philosophy of improvement that values defect prevention over defect detection. It drives customer satisfaction and bottom-line results by reducing variation, waste, and cycle time, while promoting the use of work standardization and flow, thereby creating a competitive advantage. It applies anywhere variation and waste exist, and every employee should be involved.'
Six Sigma is a complex theory – and is used widely today to improve processes across industries and sectors. Six Sigma is also used within the healthcare sector and in Quality Improvement – as it can be seen to create value by empowering staff to continuously improve. The method helps people make evidence-based decisions by quantifying problems.
However, there have been criticisms levelled at Six Sigma. In their paper ‘Learning to evolve A review of contemporary lean thinking’ Hines et al levelled criticisms of Six Sigma, summarised as:
The NHS Institute for Innovation and Improvement devoted a whole white paper ‘Lean Six Sigma for healthcare’ to looking at the basic concepts of Lean Six Sigma and how this could be applied to the NHS. They have tested and used many QI strategies to create more effective change – including Lean and Six Sigma: ‘both of which have delivered promising results, particularly when combined with other tools and techniques.’
Quality Improvement has a lot to thank Bill Smith for and the methodologies and techniques that he created can be used within the healthcare sector.
“If you want to improve something, involve the people who are doing the job.”
- Bill Smith