Quality can be defined as ‘Fitness for Purpose’, i.e.- the products or service should have the right features which satisfies the customers and are thus free from failures (no complaints, no rework etc.). The product should be consistent regarding its conformance and performance which are suited to the customer. Statistically quality can be mentioned to be inversely proportional to variability. Stakeholders view quality as excellence in performance.
Quality has 8 critical dimensions based on which the quality analysis can be done.
- Performance: This refers to the primary characteristics of a product involving its measurable attributes. For example, a performance of a tablet includes its dispersion rate, hardness etc.
- Features: These are the secondary characteristics of performance. Features are an additional attribute of the product which supplement their basic function. For example, colour of the tablet, tablet shape, etc.
- Reliability: This is the probability of a product that it will not fail within the specified time. For example, the assay of a tablet remains within the specified limit during its shelf life of 3 years.
- Conformance: This is the degree to which a product meets its defined standards. Warranty claims and defect rates are measures to calculate the rate of conformance. For example, the tablet disintegrates due to packing issue therefore it fails to conform to its specifications.
- Durability: This is the amount of use/benefit we get from the product before it deteriorates and before it is rendered not suitable for further repair. Durability has technical and economic aspects. For example, the equipment can be used for 10 years before it can be determined that repair of the same is not economical.
- Serviceability: This is the competence, speed, courtesy, and ease of repair of a product. Customers prefer timeliness in dealing of their problems. For example, a service provider performs the job in a customer friendly manner in less time.
- Aesthetics: This refers to the subjective dimension of a product. The look, smell, taste and feel provides a basis of personnel judgment and reflects the individual preference. That is, aesthetics is the quality dimension which is to please customer. For example, people prefer colored materials compared to white colored items.
- Perceived Quality: This is the quality attribute relying on indirect measures. Customers do not really have an idea of the product’s true ability, but instead they tend to compare it with other brands to perceive the quality via media advertisement. For example, a product advertised by celebrities are more liked by customers than products found just lying on the shelf of a store.
QUALITY THEORIES BY QUALITY GURUS
Edward Deming
Edward Deming is honoured as the ‘Father of Quality’ for his pioneering work in Japan in the year 1950s. He had a belief in continual improvement which led to transformational theories on management, quality, and leadership. Edward Deming believed that business should not be based on price, instead it should be based on quality. Deming said that ‘Quality speaks the language of statistics’.
Deming’s 14 points on Quality Management are a set of management practices from which the organizations can benefit by improving their productivity and quality. These are interrelated processes which constitutes the components of a system. These are as follows:
Deming’s Plan-Do-Check-Act (PDCA) Cycle is a model for continuous improvement for initiating or for improving a project, for collection and analysis of data, for verifying root cause of problems and for implementation of any change.
Deming’s Chain Reaction is a continual improvement theory laid down by Deming which is an effective management system for reducing cost of the product by improvement of the quality and allowing to reward the employees as the organization prospers. The following cycle represent the chain reaction as defined by Deming:
Joseph Juran
Joseph Juran founded the American Society for Quality (ASQ) in 1946. The ‘Quality Control Handbook’ was his first edition of classic handbook published in 1951. Juran Institute was found with the aim of increasing the awareness of his principles and theories. The terms ‘internal customers’ and concept of ‘quality cost’ were introduced by Joseph Juran. The well renowned Pareto Principle (also known as 80/20 rule) was introduced by Juran. He believed that improvement in the organizations quality system can be achieved through project by project approach. The 10 steps for quality improvement laid down by Juran are as follows:
- Build awareness of the need and opportunity to improve
- Set goals for improvement
- Create plans to achieve goals
- Provide training
- Conduct projects to solve problems
- Report on progress
- Give recognition for success
- Communicate results
- Keep score
- Maintain momentum
The Juran Trilogy is an approach for cross functional management which is composed of Quality Planning (activity to develop process and products as per customer needs), Quality Control (process to evaluate quality performance) and Quality Improvement (process of improving quality performance).
Philip Crosby
Philip Crosby promoted the concept of ‘Zero Defects’. He believed that doing the process right the first time is less expensive rather than spending on repairs and reworks. He followed the following absolutes of quality:
- Prevention in quality system
- Conformance in quality
- Zero defect is the standard for performance
- Price of nonconformance is the measurement of quality
Genichi Taguchi
Genichi Taguchi is considered as the ‘Father of Quality Engineering’. He believed that targeting the nominal value is more important than lying within the specifications. Loss function, Robust design and Orthogonal arrays (design of experiments) are his major contributions in the theory of quality.
Walter Shewhart
Walter Shewhart is considered as the ‘Father of Statistical Quality Control’. He was the one who originally invented the PDCA cycle which was popularized and developed by his student Deming. He was the one who first introduced control charts and was a pioneer in statistical quality control. He observed every process to be displaying 2 types of variations- controlled (natural to process) and uncontrolled (sudden variation).
Kaoru Ishikawa
Kaoru developed quality initiatives in Japan. He not only considered top to bottom approach in an organization but also bottom up approach. He developed the ‘Quality Circle’ (group of members who perform same/similar work and meet regularly to identify, analyze and solve quality problems) and also innovator of the Root Cause Analysis also called as Fishbone diagram.
Armand Feigenbaum
Armand Feigenbaum was responsible for promoting the concept of ‘Total Quality Control’. He is the innovator of Quality Cost Management. He defined Quality Costs as internal failure cost, external failure cost, prevention cost and appraisal cost.
Bill Smith
Bill Smith is considered as the ‘Father of Six Sigma’. His approach was to reduce variability in a process to reduce defects and increase the profit of an organization. He believed that data collection and other statistical approach are significant for quality improvements which were implemented in the 1980s in Motorola.
Mikel Harry
Mikel Harry has been recognized as the ‘Principle Architect of Six Sigma Methodology’. He developed Define, Measure, Analyze, Improve and Control approach (DMAIC) which is used in Six sigma methodology. The six-sigma belt concept (yellow, green, black, master black belt) was introduced by Mikel Harry.
Eliyahu Goldratt
Eliyahu Goldratt is known as the originator of the ‘Theory of Constraints’ (TOC). TOC is a management methodology in which the perspective is that in a management system it gets bound to achieve limited goal due to very small number of constraints. At least one constraint is always present in a system which should be identified and restructured to improve the system.
Masaaki Imai
Masaaki Imai is known for introduction of ‘Kaizen’ which is a Japanese word meaning improvement. Kaizen represent small, incremental improvement rather than a sudden improvement to make it sustain for a longer period.
Taiichi Ohno
Taiichi Ohno is known as the ‘Father of the Toyota Production System’ which is now known as Lean manufacturing. He defined the seven types of wastes namely the transport, inventory, motion, waiting, over processing, over production and defect waste.
Noriaki Kano
Noriaki Kano is known as the ‘Developer of Kano Model’ (customer satisfaction model). Kano model can be used to differentiate between the differentiating and essential attributes related to customer quality concepts.
Yoji Akao
Yoji Akao is known as the originator of the concept of ‘Quality Function Deployment’ (QFD). QFD is used to effectively identify and prioritize expectations of the customers and aids in transforming the Voice of the Customer (VOC) into engineering characteristics for a service or product. ‘Hoshin Kanri’ has also been promoted by Yoji Akao.
Shigeo Shingo
Shigeo Shingo is famous for introduction of the concept of ‘Poka-Yoke’ which is a Japanese word meaning mistake proofing. Poka-Yoke are controlling mechanisms whose main purpose is elimination of mistakes by helping operators to detect and eliminate defects. Just in time (JIT) strategy was also introduced by Shigeo Shingo which is helpful in reducing inventory load.
All the aforesaid mentioned Quality Gurus played an incredibly significant role in defining and developing the quality tools and techniques which are now widely used in various organizations to improve the quality of the products