Quality control (QC) refers to the most traditional form of quality management in which a supervisor or inspector periodically checks and examines output for possible defects, usually at the end of the production process. Quality controllers aim to ensure the products comply with quality standards. They are specialist inspectors, so are hired to maintain quality standards. For mass produced products, QC is usually conducted in a systematic way, such as once every hour or every 100th unit of output. For highly expensive products, such as a Ferrari or Bugatti, each one is checked to ensure quality standards are met.

 Advantages of quality control

The advantages of QC include the following points:

• Quality control prevents substandard (poor quality) output reaching the end-user.

• Quality controllers are experts, so should help to ensure fewer mistakes are made.

• It is also cheaper than quality assurance as fewer workers need to be trained to check for quality.

 Disadvantages of quality control

Disadvantages of quality control include the following points:

• QC is a reactive rather than proactive method of quality management, so does not prevent mistakes

• If products are only checked at the end of the production process, this can result in a rather large volume of substandard products

• Quality control also has an accepted reject rate (given that it is not possible to check every unit of output), unlike in quality assurance where the aim is to achieve zero defects.

Quality assurance (QA) is a lean approach to quality management as it involves all employees in the quality process. QA focusses on empowering all staff to check their own work throughout the production process, rather than relying on quality controllers to inspect the final output. This approach to quality management considers quality in every operations decision in order to prevent mistakes, from product design to the level of customer service and timely distribution to customers.

 Advantages of quality assurance

The advantages of quality assurance (QA) include the following points:

• It can improve the level of motivation in the workplace as employees are given the responsibility to produce and maintain high quality output.

• Employee participation can also help to generate new ideas regarding the quality process.

• It reduces the costs of wastage and reworking of substandard products.

• QA is proactive and preventative, unlike QC which is reactive (to faults and defects).

Disadvantages of quality assurance

The main drawbacks of QA include the following points:

• It is expensive compared to quality control, as all workers are involved and need to be trained or upskilled

• The philosophy only works if each staff member is committed to quality assurance.

• For some organizations, it is not feasible or suitable to ensure each and every product is checked or inspected.

• Quality means that a product is fit for purpose, i.e., the good or service meets or exceeds the needs of its customers.

• Quality assurance (QA) is a lean approach to quality management which involves all employees in the quality process. It focusses on empowering all staff to check their own work throughout the production process, rather than relying on quality controllers to inspect the final output.

• Quality control (QC) is an approach to quality management that involves quality inspectors periodically checking and examining output for possible defects, typically at the end of the production process.

To test your understanding of this topic, have a go at the exam practice question below.

Exam Practice Question

Distinguish between quality assurance (QA) and quality control (QC).  [4 marks]

 Teacher only box

Answer

Quality control (QC) is a quality management system whereby a product’s quality is checked or tested at the end of the production process. Quality inspectors or quality controllers are responsible for examining a sample of the finished products to assess whether they meet the required quality standards.

By contrast, quality assurance (QA) is a quality management system whereby the quality of the product is conducted throughout its entire production process. QA is a philosophical approach to quality management, involving all employees at every stage of production, thereby helping to identify and/or prevent defective output.

Award [1 - 2 marks] for an answer that shows some understanding of the demands of the question, although there is a lack of detail in parts of the answer.

Award [3 - 4 marks] for an answer that shows good understanding of the demands of the question, similar to the example above. There is effective use of appropriate terminology throughout the response.