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'Zero Defects' Manufacturing: how the manufacturing industry aims for perfection

Written by Kitty van Commenee | Mar 26, 2024 3:58:00 PM

What is zero defects?

How many dfects are allowed in a design? How many complaints are too many? How many products may have a deviation? The ideal answer is: none. But that's not how it works because making zero mistakes is virtually impossible. And yet, that's the goal with 'zero defects production'.

Zero defects is a system for production and quality management. The principle: creating an organization where no mistakes are made. The idea behind Zero Defects is to pursue perfection in all aspects of the production process, from design to final delivery to the customer. Proponents argue that it promotes a culture of quality, employee engagement, and continuous improvement to meet the highest standards of quality and customer satisfaction.


The origin of the zero defect principle

Zero defects is one of the principles from the book Absolutes of Quality Management by American engineer and pioneer in quality management Philip Crosby. He has made significant contributions to the development of modern quality practices in the industry. He started his career at Procter & Gamble, where he worked as a quality manager and where he developed a thorough knowledge of quality processes.

Crosby strongly believed in the importance of preventing mistakes rather than correcting them after they occurred. This led to his famous mantra: "Do it right the first time". In his book Quality is Free, he further elaborated on the principle of 'zero defects' production. He argued that preventing mistakes not only improves the quality of products but also saves costs that would otherwise be spent on correcting errors and handling customer complaints.

Crosby's approach to Zero Defects received global recognition and was adopted by many companies worldwide. Even today, many of his ideas form the basis of modern quality management. Zero defects production is often mentioned in conjunction with lean working.

The basic principles of zero defects production

The idea of zero defects production is based on several basic principles, including the belief that defects are not inevitable, that prevention is better than correction, and that every employee plays a role in achieving the goal: zero defects in production. By applying these basic principles, Crosby believed that organizations would be able to deliver consistent quality, improve customer satisfaction, and reduce costs by preventing mistakes and striving for zero defects.

Quality is free

Quality is free - or Quality is Free. Crosby argued that preventing mistakes ultimately costs less than correcting them. He emphasized that investing in error prevention, such as through training, process improvement, and preventive measures, leads to long-term cost savings.

Zero defects

The foundation of zero defect is the pursuit of zero errors in all aspects of production and service. This means not only eliminating defects in the final product but also preventing errors throughout the process, from design to delivery. Quality control naturally plays an important role in this.

Quality awareness

Crosby emphasized the importance of creating a culture of quality awareness within an organization. This includes involving all employees in the pursuit of quality, providing training and support, encouraging responsibility for quality, and recognizing achievements in quality.

Do it right the first time

Crosby advocated for the importance of striving for perfection from the beginning. He believed that correcting mistakes is costly and ineffective. Therefore, it is essential to design and execute processes that aim to prevent errors and deliver a perfect product.

Committed management and employees

Crosby stressed the importance of management involvement in the pursuit of quality. He believed that leadership and management involvement are essential to create and maintain a culture of quality within an organization. Employees are also encouraged to actively participate in the pursuit of zero defects. This can range from identifying potential problems to suggesting improvements in processes and procedures.


Defects per million opportunities (DPMO)

The effectiveness of a zero defects policy can be measured with Defects Per Million Opportunities, or DPMO, a measurement tool used in quality management to quantify the performance of a process based on the number of defects that occur per million opportunities or possibilities. The term is central to the teaching of zero defects production.

Defects refer to any error or deviation from the specifications that occurs during the production process. It could be a defective product, but also an error in a process step. Per Million opportunities refers to the total number of chances for errors to occur in the process.

A 'chance' can be defined as a unit of work or a process step where an error can occur. The number of opportunities is often normalized to a million to provide consistency when comparing different processes.

You can calculate the DPMO in your organization relatively easily by following these steps:

  • Identify the number of defects that occurred over a given period.
  • Identify the total number of chances or opportunities for errors that existed during the same period.
  • Calculate the number of defects per million opportunities using the formula: (Number of defects / Total number of opportunities) * 1,000,000.

Aiming for the lowest possible DPMO number is in line with the Zero Defects philosophy. A DPMO of zero means that no defects occurred in the process, which means that the perfect quality pursued in a zero defects approach has actually been achieved.

Criticism of the zero defects method

Making no mistakes is a noble pursuit. But how realistic is it? It won't surprise you that there is also quite some criticism of the zero defect method.

Unrealistic objectives

The most common criticism of zero defects is that striving for zero errors is often unrealistic. This is especially true in complex production processes or in situations where human involvement is a factor. Despite extensive efforts and investments, it is virtually impossible to prevent every possible mistake. Striving for zero errors is a goal in itself, but it makes the production process, and the quality management of it, so much more intensive and difficult that the end doesn't justify the means.

Costs and benefits

Applying the Zero Defects principle comes at a cost, both in time and resources. It's important to find a balance between the costs of quality improvement and the potential benefits for the organization.

Focus on process rather than innovation

Striving for zero defects can lead organizations to focus too much on perfecting existing processes rather than investing in innovation and growth. An excessive emphasis on error prevention can lead to a lack of flexibility in a rapidly changing business environment.

Demotivating for employees

If zero errors is the only acceptable outcome, employees become stressed and demotivated. This happens, for example, when errors are inevitable due to complex processes or external factors beyond employees' control. Too strong a focus on a flawless production process can lead to a culture of fear and risk avoidance.

No focus on customer needs

The idea is that zero defects leads to the most satisfied customers, but is that so? Focusing on eliminating internal errors can ensure that there is too little attention for customer interest. It is certainly possible that pursuing perfection does not lead to improved customer satisfaction or the best products.

Getting started with zero defects

Want to get started with zero defects production? Start with the books of Philip Crosby. And remember: the zero defect method can be effective, but don't see it as a so-called 'holy grail'. It is more a cultural change that can benefit your organization. Because although 100% perfection is almost impossible, striving for it in itself is a good goal to aim for.