Quality Control vs. Quality Assurance: Demystifying the Differences

Quality assurance and quality control are often used interchangeably. However, these concepts are unique components of the software development lifecycle.

Quality assurance (QA) aims to prevent defects through systematic and planned activities such as process standardization, improvement and documentation. Quality control (QC) uses software testing and inspection to identify existing defects and ensure that software meets specified standards.

Quality is the backbone of the development process. Putting low-quality software in the hands of end users leads to several problems, including failure to meet customer requirements and damage to brand reputation.

Although these process-oriented activities are different, they work together to improve the software. They also enable development teams and project managers to implement effective strategies to manage quality across the SDLC.

Quality Control (QC): Definition and Overview

Quality control is the process of finding and correcting defects in completed products to meet the quality standards required by the project. Quality control activities are reactive and help identify deviations from pre-specified criteria or problems. QC aims to ensure that software is as defect-free and usable as possible.

Key Features of Quality Control

QC primarily focuses on ensuring that each product meets established standards and specific requirements at a specific product level. As a reactive process, it is implemented after active development. This is one of the main differences between QC and QA.

To maintain high levels of quality post-development, this test-centric methodology encompasses many different types of testing, such as performance, usability, and functionality testing. These tests help quality control professionals identify inconsistencies, defects and cases of non-compliance with quality standards. By taking a comprehensive approach, QC ensures the reliability and integrity of a product before consumers can access it.

Quality control tools and techniques

Quality control professionals employ a variety of tools and techniques to test the quality of a product. Popular tools for tracking and reporting issues, like Bugzilla and JIRA, help you better manage testing efforts, allowing testers to document, assign, and resolve issues more efficiently.

Testing categories include manual testing, which requires human involvement and is often highly detailed, and automated testing, which aims to improve speed and consistency and requires tests to be scheduled. Regression testing, which is usually automated, ensures that new changes do not negatively affect existing functionality.

There is also the option to choose from various quality control testing methodologies such as Six Sigma, Lean Production and Total Quality Management. QC testers often combine these tools, techniques, and methodologies.

Benefits of quality control

The overall goal of QC is to ensure that software meets requirements, regulations, and quality standards before release. It benefits companies and consumers. It also increases brand reputation, promoting customer trust and loyalty.

Limitations of QC

There are some limitations to CQ. The biggest restriction is that it is not possible to 100% guarantee that the software is free from defects. Even after rigorous testing and inspection processes, some defects remain undetected due to a variety of factors.

Additionally, QC can be time-consuming and expensive, with significant resource requirements. In some cases, this affects project schedules and budgets.

Quality Assurance (QA): Definition and Overview

The main objective of quality assurance activities is to ensure that quality is maintained throughout the development process. This involves preventing defects from the beginning of the development lifecycle. It emphasizes maintaining quality throughout development.

Through regular audits, process evaluations, and development best practices, the quality control process helps ensure that the final product meets quality standards without requiring corrective measures after development is complete.

Key Quality Control Features

By focusing on planning, defining and refining processes, quality control helps prevent defects before they affect the final product, rather than reactively identifying problems after development.

Successful quality control involves regular training sessions for team members, comprehensive process documentation, and the goal of continually improving processes. By incorporating quality into every part of the development process, quality control facilitates the consistent delivery of high-quality products and increases consumer confidence while reducing the likelihood of post-development defects.

Quality control tools and techniques

To make the QA process more efficient, QA professionals employ a variety of tools and techniques to maintain software excellence, quality, and reliability.

TestRail, for example, makes managing and tracking test cases easier and more effective. Selenium, a well-known name in the testing world, helps QA teams automate their testing for quality.

Creating a successful quality control strategy involves utilizing several techniques. Setting standards establishes clear quality criteria, while process design increases the efficiency of overall operations. Process audits evaluate a product’s adherence to quality standards. Used together, these tools and techniques help quality control teams preemptively identify and correct defects.

Benefits of quality control

Quality control plays an important role in software development, ensuring that the software meets high standards. This reduces the need for costly post-development fixes while simplifying the overall development cycle.

Through its proactive nature, QA allows development teams to fix problems early in the process. Companies decrease time to market and save costs through more efficient resource allocation. Users enjoy more reliable software, which helps increase trust and satisfaction.

Limitations of quality control

Quality control is an indispensable part of the development process. However, it is not without limitations.

Establishing quality control standards and processes requires a significant initial investment in terms of resources, time and training. Some consider quality control to be an overly cumbersome and bureaucratic process, saying it can stifle creativity and slow down the development cycle.

Although quality control aims to prevent defects, it does not eliminate the need for quality control. Quality control allows teams to identify and correct any defects missed by quality control processes. Using both processes together is the best way to ensure that the final product meets all necessary standards and has as few defects as possible.

Quality Management: The Global Framework

Quality management (QM) is a combination of QA and QC. This approach helps improve the quality of products and services across the company. By embedding quality into organizational culture, QM helps teams align quality processes, policies and objectives with the organization's goals and direction, while enforcing adherence to quality standards.

QM's relationship with QC and QA

A more holistic approach to achieving high quality standards, QM unifies the practices and principles of QA and QC into a unified approach. It also encourages standardization and process improvement.

Although QA and QC are distinct processes, they are interconnected and equally important aspects of an effective QA framework. Together, they incorporate quality into the development process from the beginning and foster a philosophy of continuous improvement.

Key elements of quality management

QM has four main components. Together, they provide a model for achieving quality.

1. Quality planning focuses on establishing quality goals and allocating the resources and processes necessary to achieve them.
2. Quality Assurance ensures that established processes are sufficient to meet quality standards.
3. Quality control involves inspection of final products against quality criteria to detect any defects.
4. Quality improvement is a continuous effort to improve services, products and processes based on feedback and evaluation from the comprehensive QA process.

Why QM in software development? Benefits and Challenges

QM not only improves customer satisfaction and process efficiency, but also plays a key role in reducing waste while ensuring consistency.

Adhering to QM helps organizations across industries develop a systematic approach to ensuring quality, encompassing both QA and QA. It also leads to more robust quality systems, better risk management and a culture of continuous improvement. Additionally, it helps companies achieve compliance with quality-related industry standards.

One of the greatest strengths of a QA framework is its ability to address common challenges such as change management, balancing standardization and flexibility, and resource allocation. QM helps organizations adapt to changes while meeting quality standards. It also nurtures a culture of quality at all organizational levels.

Through a more comprehensive view of quality in the industry, companies can build more robust and efficient software.

Quality Control vs. quality assurance: a comparison

Although they are different processes, QA and QA aim to help companies produce high-quality software that meets industry standards.

Quality control takes a proactive approach to quality with the goal of preventing defects in advance through systematic processes and standards. QC, the Yin to QA's Yang, focuses on a reactive approach, detecting post-development defects through careful inspection and testing. Used separately, these processes are somewhat effective. However, when used together, QA and QC contribute to a more robust, quality-oriented culture.

Conclusion

Quality assurance and control are important processes to ensure product quality. By leveraging them together, they help contribute to better products across multiple industries. Leveraging both processes through a quality management approach gives companies a reliable means of ensuring quality throughout development.

Common questions

What is the main objective of quality control?

The main purpose of quality control is to detect and correct defects in a finished product. The process is used across industries.

Why is quality assurance considered proactive?

Quality assurance is considered proactive because it consists of processes carried out to prevent defects from occurring.

Can organizations rely on QA alone or QA?

QA and QC have their own purposes and benefits. While it's possible to rely on just one or the other, companies typically get more comprehensive coverage when they use them together.

Are QA and QA only applicable to software development?

No, QA and QA are not specific to software development. These processes are applicable to a wide range of industries, helping them improve the quality of products, processes and services.

Are statistical process control (CEP) and statistical quality control (CEQ) used in software development?

While SPC and SQC are traditionally associated with manufacturing and production, the concepts behind these processes are often applied to software development to help ensure quality. The SPC can be adapted to monitor different aspects of the SDLC, including code quality and defect rates. SQC can be applied to inspect and evaluate the quality of final software.