What is Quality Control (QC)?
Quality control (QC) is the process of quality checks, quality plans, and automated hold points in every stage of the function of the organization to ensure the quality of products and services.
It helps to measure actual work completed with that of standard determined and to find out deviation, if any, in actual performance. If any deficiency is found in actual work management can the corrective measures on time to maintain standards of performance and quality.
Quality control involves maintaining inspection in all the operational areas of the organization. Quality improvement initiative is not possible without a means of monitoring and evaluating each stage of progress. Authority needs to make supervision standards for inventory control, defect rate, raw material procurement, or other operation management areas, and where improving quality is important.
For example, manufacturing organization focuses on quality assurance through continuous research by trained expertise, installation and use of modern instruments, procurement of raw materials only from authentic sources, and extensive testing of the procured materials using formal tests, etc.
Today the quality of a product or service defines the success and failure of the organization. Thus, management needs to take all necessary steps to maintain the quality of goods and services in order to achieve competitive advantage and customer satisfaction.
Methods of Quality Control
There are two main techniques of quality control systems consisting of inspection and statistical quality control.

Inspection (Review)
Inspection is concerned with periodic supervision of the performance of subordinates to maintain the quality of products and services.
In every job unit of the organization, there should be the provision of functional experts to maintain inspection and supervision over the performance. The function of the supervisor is to maintain the quality of products and services. For this purpose, proper instruction and guidance should be given to subordinates before starting work.
In addition, in the course of doing work, it is necessary to observe whether a predetermined quality standard is maintained or not. Therefore, supervisors need timely supervision to maintain the performance of subordinates to know about any defects in their working procedures, techniques, and system.
If in the course of doing work, any deficiency is found in the performance, supervisors need to resolve defects by doing corrective measures. Such technical assistance becomes supportive to the employees to improve their present and future quality of work.
The improvement of employee efficiency helps for proper utilization of resources, minimizes wastage, and maintains the quality of products and services. Inspection of performance is the continuous task of the supervisor up to the existence and functioning of the organization.
Statistical Quality Control
Statistical quality control is the sampling and probability technique to maintain the quality standard of products and services.
It is a quantitative tool for quality control. In this method, sampling and probability technique is used to measure and maintain quality standards of products and service.
In this technique, information is collected about the actual quality of work, analyzes such information by using different statistical tools, and compared that with of determined standard.
It supports the manager to know whether actual performance is going in accordance with a predetermined standard or not.
The main motive of statistical control is to maintain control over the quality of materials, working procedures, parts, and products through the use of samples. This provides guidance to the manager to know the quality of actual performance.
The manager can compare the quality of actual performance with that of the standard defined and if any deficiency is found in actual quality, they can take corrective measures. This will be supportive to improve the quality of future performance.
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