If your organization is known for its high-quality products and services, then you should perceive that as a good thing. But did the concept of quality control help you get there? Let’s explore what quality control really means.
Quality is often defined as having your products or services meet your customers’ specifications or expectations. Control can be defined as the act of having influence over some outcome. Control can also be defined as the testing or verification of actual results by comparing it to some defined standard. Therefore, you might start defining quality control as the act of influencing the quality of your organization’s products or services.
Overview: What is quality control?
Quality control (QC) is a reactive process intended to detect defects or non-conformities. QC ensures that your approaches, techniques, methods, and processes are correctly followed. QC activities monitor and verify that your deliverables meet the defined quality standards, customer expectations, and specifications.
A similar concept that is often confused with QC, is quality assurance (QA). Quality Assurance focuses on preventing defects. QA ensures that your approaches, techniques, methods, and processes are properly implemented.
QA is a proactive process and oriented towards prevention rather than detection. Activities monitor and verify that your processes used to produce and deliver your products and services have been properly followed. Over the decades since QC and QA developed, there have been several definitions related to quality. Here are a few:
| Terminology | Approximate year of first use |
| Statistical quality control (SQC) | 1930s |
| Total quality control (TQC) | 1956 |
| Statistical process control (SPC) | 1960s |
| Company-wide quality control (CWQC) | 1968 |
| Total quality management (TQM) | 1985 |
| Six Sigma (6σ) | 1986 |
| Lean Six Sigma (LSS) | 2001 |
Here is more detail on the differences between QC and QA:
An industry example of quality control
After depending on QC for many years to make sure the company shipped quality products, the CEO implemented Lean Six Sigma (LSS) to shift the thinking from inspection to prevention. After deploying LSS for 5 years, the company was able to disband the formal QC department and used LSS tools and operator focused quality checks to assure they were delivering high quality products to their customers.
One of Dr. W. Edwards Deming’s famous quotes helped convince them to change their ways. The quote was:
Frequently Asked Questions (FAQ) about quality control
Is QC and QA the same thing?
No. QA and QC are not the same. While both are linked and sometimes difficult to distinguish, they are different in origin. QA and QC both are part of Quality Management. However, QA is focused on preventing defects while QC is focused on identifying the defect.
What is the most common form of QC?
Inspection is probably the most common technique used for QC. It’s the process of examining and testing a product or service to check if it complies with specified internal or external requirements.
Should the quality manager report directly to the manufacturing manager?
While this is occasionally done, it is not a good idea. There is a built-in conflict of interest between the two functions. Manufacturing typically wants to get products out the door even if the quality might not be perfect. Quality wants the best products to be shipped even if production has to slow down or product needs to be rejected.
