What is quality assurance in software development?

Quality assurance (QA) is a continuous process through which companies determine whether or not a product or service meets specified requirements. It touches every part of a product’s lifecycle, from when standards are first set before the work begins to when they are reevaluated after the product launch.

QA is important in every field. It ensures that customers get products that are free from defects and work as intended.

In the software industry, buggy software that frequently fails to perform can hurt a brand’s reputation. The company may find it hard to reestablish trust with customers. In contrast, bug-free, easy-to-use software can provide a strong advantage over competitors.

Take a close look at quality assurance in this article, exploring how it relates to similar processes, how it is used in software development, and the QA best practices your company can implement to improve.

Quality assurance is a comprehensive and systematic process that helps companies consistently deliver value to customers—its core objective. It starts with a set of specific standards and requirements and puts processes in place throughout a product’s lifecycle to ensure they are met.

QA’s broad goal of delivering value to customers can be broken down into smaller parts:

• Identifying and mitigating risks: QA looks for potential risks or defects in a product or service and implements measures to mitigate them. Requirements will often be updated to take these risks into account.

• Process optimization: QA addresses problems with production or service delivery as they arise and updates standards and procedures to ensure better quality outcomes in the future.

• Enhancing product quality: QA is a continuous process. It still looks for ways to enhance product quality even when there are no problems to address. For example, it keeps pace with the latest technical advances to help avoid problems and provide value.

Involving regular monitoring and auditing, QA plays a key role in maintaining standards. Any existing industry standards will be baked into a product’s requirements. As opportunities to improve arise, QA provides companies with the tools to create internal standards that set them apart from their competition.

This effort results in a product or service built on loyalty and trust that meets or exceeds customer expectations. A good QA process will incorporate a customer feedback loop, taking customers’ suggestions and pain points as input to improve the product.

Quality assurance and quality control (QC) both play important but distinct roles in quality management.

QA is a proactive approach. It’s about preventing defects or problems in a product or service before they occur. It focuses on procedures and activities during the production process that will minimize the risk of error and maximize the chance of the product fulfilling its expected functionality.

QC, on the other hand, is a reactive process. It involves understanding that no matter how careful the QA and production teams are, the final result will inevitably contain mistakes. QC aims to identify those defects and rectify them before the product or service reaches the end user. It accomplishes this through testing and inspection to ensure the final result matches the requirements established during QA.

Although both processes are distinct phases of the project, they help to inform one another. Problems found during QC can often be mitigated by refining the processes in the QA stage. Potential problems discovered during the QA phase are good things to test during the QC phase to ensure they were successfully mitigated.

Software development is a complex process, often involving very large codebases with strong dependencies on one another. There’s always the potential to miss a dependency and introduce a bug, small or large. QA plays a critical role in preventing that from happening and aims to provide users with a functional and reliable piece of software.

As with other fields, QA plays a role in software development throughout the product’s lifecycle. It starts in the initial phases, setting functionality requirements and design specifications. During the coding phase, QA ensures coding standards are adhered to and continuously reviews code to spot any potential bugs or other issues.

QA also plays a role in the testing phase, setting out guidelines for unit tests and other test procedures to catch any remaining bugs before release. Post-launch, it can help identify any remaining issues—hopefully before a customer does.

Much like QA and QC, software quality assurance (SQA) and software testing are related by distinct processes in software development.

SQA is a broad process-oriented approach that covers the entire software development lifecycle. It aims to create development processes that, when followed closely, are more likely to result in a product that has the required features and minimal defects.

SQA involves the following:

• Process definition and implementation

• Auditing

• Training

• Strategies for improving processes as the need and opportunity arise

Software testing is product-orientated, not process-oriented. It involves the execution of automated or manual tests that identify bugs or defects in the product. In this way, it’s the verification aspect of SQA. The tests performed ensure the software performs all the functions listed in the QA requirements correctly. It also searches for bugs, particularly those that may have been identified as potential issues during earlier QA phases.

In simple terms, SQA focuses on creating processes that prevent bugs or fixing them as they arise, while software testing focuses on finding any that slip through the cracks. Together, QA and SQA help stop you from releasing buggy software to customers.

Here are some of the methods businesses use to implement quality assurance. The QA methods below aren’t mutually exclusive; a company can put two or more of them to work.

Total quality management

Total quality management (TQM) is a holistic approach to quality management. It aims to integrate all company functions—including marketing, finance, design, engineering, and customer service—with a focus on meeting customer needs and objectives.

TQM works on the assumption that all areas of the company can contribute to the quality of customer experience in some way. The goal is to go beyond traditional QA methods and establish a culture of customer satisfaction among all employees. To do this, TQA emphasizes the need for fact-based decision-making that centers on the customer experience. A strong focus is placed on cross-functional teamwork and communication to keep everyone on the same page.

Failure testing

Although software developers wish it weren’t the case, there’s always a chance that the software will crash. It’s sometimes possible to predict the conditions under which this can happen. A system might not be designed to work well beyond a certain capacity, for example. Failure testing, also known as fault testing, intentionally pushes the software past that point.

By purposefully crashing the software, testers can see how well it recovers from the crash. For safety-critical systems, in particular, even a software crash must occur safely and minimize negative consequences. Awareness of the types of situations that can lead to this and planning for them properly enable developers to increase their product’s safety.

Process and product quality assurance

As its name implies, process and product quality assurance (PPQA) is a systematic approach that focuses on ensuring the quality of the following:

1. The processes used in product development (process quality)

2. The product itself (product quality)

In a PPQA framework, specific requirements and standards are carefully researched and laid out for both. Teams perform regular audits and reviews to ensure those requirements are being met.

PPQA is a good way to identify deficiencies in a process or defects in a product and implement corrective actions. It allows requirements to be continuously refined to ensure quality is always trending in the right direction.

Capability maturity model integration

Capability maturity model integration (CMMI) is a QA approach built on the idea that processes at different stages of maturity need to be handled differently.

CMMI defines five stages of maturity:

1. Initial

2. Managed

3. Defined

4. Quantitatively managed

5. Optimizing

In its early stages, for example, a process is less clearly defined and may seem a bit chaotic. As it goes through various stages of maturity, it becomes more refined, and the bulk of the work in managing it will evolve into continuous refinement and minor adjustments.

Viewing processes in this way allows QA teams to better manage their priorities, set improvement goals, and expend resources where they will be most beneficial. This makes CMMI a highly adaptable framework capable of helping businesses of all sizes.

Statistical process control

Originally designed for use in manufacturing, statistical process control (SPC) has also found its way into other industries. It involves using statistical methods to monitor and control a process.

When using this method, companies can determine whether a process is functioning with set parameters and whether it’s capable of consistently producing the desired quality level.

The first step is defining the data type needed to evaluate the process. The next is to collect it. The data is then plotted and tracked over time. SPC’s goal is to keep the data variation to a minimum and keep the values within an acceptable range.

Quality assurance efforts can make a significant difference in the quality of your products or services. However, not all QA efforts have the same effect. To get the most out of quality control, you need the right teams and processes for your organization in place. The tips below will help you get started.

Establishing a QA team

QA is a complex process that deserves a skilled and dedicated team. The QA team should consist of people with diverse expertise across various aspects of quality control within your industry. This will allow them the breadth of knowledge required to properly identify potential issues and develop processes around them.

The team should be empowered with ongoing training opportunities to stay up-to-date on the latest methodologies and tools.

For a more holistic approach, encourage collaboration between the QA team and other departments.

Developing robust evaluation criteria

The bulk of quality assurance is about making sure that processes and products align with evaluation criteria. Therefore, the process relies heavily on having clearly defined criteria that align with both customer and business expectations. These criteria should cover all aspects of the product or service, including functionality, security, performance, and usability.

By establishing standardized procedures for all these areas, QA teams can provide a consistent and objective framework to measure the success of processes and the quality of their end results. However, it’s best to view these standards as living documents, updating them when necessary.

Leveraging technology for improvement

It’s always important for companies to stay on top of the latest technological advances. Technology plays a critical role in the quality assurance field. The capabilities of tools like automated testing, continuous integration, and quality management software continue to improve. These tools can significantly enhance the effectiveness of QA efforts.

The automation these tools provide enables teams to perform even more rigorous testing that’s easier to repeat. They also provide data analytics that reveal insights that might otherwise go unnoticed.