The Importance of Requirements Quality in Software Development

In software development, having clear and high-quality Requirements is crucial. If the requirements are not well-defined, it can lead to problems later in the development process, potentially causing defects and increased costs. This makes the study of requirements quality very important.

However, the field of requirements quality research is facing challenges. There is a lack of a clear identity and structure in the research community, which hinders progress. Recent attempts to address these issues have highlighted the complexity of understanding requirements quality. It is important to have a clear theory about what makes requirements high quality, to evaluate the current state of research, and to provide guidance for future work in this area.

#Importance of Requirements Quality

High-quality requirements can greatly reduce the risk of defects as the software development process moves forward. The quality of requirements directly affects the success of software projects and how well they stay within budget. If defects are introduced early in the requirements phase, they can become more expensive to fix as time goes on. Therefore, it is essential to find effective ways to ensure the quality of requirements from the start.

Research in requirements quality aims to improve how requirements are written, understood, and utilized in software projects. To do this effectively, researchers need to look at not just the requirements themselves, but also how they affect the Activities that follow in the software development process.

#Current State of Requirements Quality Research

Despite the important role of requirements quality in software development, many existing theories and frameworks are too abstract to be practically useful. They often categorize quality into sub-categories without providing clear applications. A more practical approach is needed to connect requirements quality to its effects on later software activities.

In this article, we propose a new theory that organizes the key concepts of requirements quality. We also evaluate how current research aligns with this theory and outline a roadmap for future research that can make the field of requirements quality more relevant and effective.

#Evolution of Software Quality Research

To understand the development of requirements quality research, it helps to look at how software quality research has evolved. Both fields share the goal of ensuring the quality of Artifacts used in development, which Impacts the overall success of projects.

#Guidelines and Metrics

One of the simplest ways to control software quality is through guidelines. For instance, coding conventions dictate how to name and structure code files. However, these guidelines often do not significantly improve quality because they are not adequately justified or assessed in practice.

Metrics-based approaches emerged to measure software attributes using specific metrics. For example, measuring lines of code or complexity can help assess software quality. However, many metrics lack clear justification for their relevance.

#Quality Models

Quality models build on metrics by organizing them into broader criteria. These models attempt to justify why certain metrics are important for overall quality. For example, concepts like "structuredness" and "conciseness" of code can be linked to broader characteristics like "understandability" and "maintainability."

However, these models can be overly complex or too abstract for practical use. There is often a disconnect between the metrics and their rationale, making it hard to apply them effectively.

#Activity-based Quality Models

Activity-based quality models attempt to overcome limitations of previous models by separating properties of the system from properties of the activities in which the system is used. These models analyze how system properties impact the activities that utilize them, providing a clearer picture of quality.

Despite their complexity, activity-based models aim to clarify the concept of quality and its implications for software development. They have been successfully applied in areas like usability and security.

#Linking to Requirements Quality Research

Similar to software quality, research in requirements quality began by proposing metrics associated with poor quality. Over time, it became clear that many of these metrics lack a connection to their real impact on software activities.

Existing quality models for requirements often remain vague about how quality factors influence actual software activities. There is often limited exploration of these impacts in practice, which hampers the adoption of quality models in the industry.

#Activity-based Requirements Quality

Some researchers have recognized the need to adopt an activity-based approach in requirements quality. Studies have shown that the quality of requirements affects the activities that depend on them. However, the application of this approach has not been widespread, and many researchers still focus on artifact-centric views of quality.

#A New Theory for Requirements Quality

In this article, we propose a harmonized requirements quality theory (RQT) that draws on the evolution of software quality models. The RQT combines the insights gained from software quality research with the needs of requirements engineering.

#Key Concepts of the RQT

The RQT consists of several key concepts. It defines what a requirements artifact is, identifies relevant activities that impact quality, and establishes how these elements interrelate.

1. Artifacts: These are the actual requirements documents or specifications. They can be broken down into smaller units, such as sections or sentences.
2. Activities: Activities are any processes that utilize requirements as input, such as validation or analysis.
3. Impact: The theory emphasizes the impact that requirements quality has on the effectiveness of activities. The relationship between quality factors and activity outcomes is crucial.

By focusing on how these concepts interact, the RQT provides a more practical framework for understanding requirements quality.

#Example Application of the RQT

To illustrate the RQT, consider a requirements specification that includes a user story. A quality factor might dictate that the user story must follow a specific template. If the template is not followed, it can create ambiguity during the subsequent activity of understanding the requirement.

The relationship between the quality of the user story and how well it is understood demonstrates the impact of requirements quality. A lack of clarity can lead to misunderstandings, affecting the correctness of the software developed.

#Evaluating Current Research

To see how well the current research aligns with the RQT, we conducted a survey of recent literature on requirements quality. This survey aimed to identify how deeply the concepts of the RQT are represented in existing studies.

#Findings from the Survey

The survey revealed that while requirements entities and factors are commonly mentioned, there is a noticeable lack of attention to the impact these factors have on activities. Many publications neglect to report how specific quality factors affect the understanding and processing of requirements.

Most studies focus on the quality of requirements artifacts but fail to connect these Qualities to the practical activities where they are used. This limits the relevance and applicability of the research findings.

#Implications of the Findings

The survey's findings underscore the need for a more balanced approach in requirements quality research. Greater emphasis should be placed on understanding how quality factors influence subsequent activities. Ignoring this connection risks leaving the proposed quality factors as mere guidelines without practical significance.

By adopting the RQT, researchers can better articulate the relationships between requirements quality and the activities they influence. This would enhance the practical relevance of requirements quality studies, making them more useful for industry application.

#Research Roadmap for Advancements

To further develop the field of requirements quality research, we propose a research roadmap that outlines key areas for future study.

#1. Reference Artifacts and Usage Models

Creating a set of reference artifacts and usage models can help standardize the understanding of entities, activities, and agents involved in requirements engineering. This foundational work can guide the industry and researchers in their efforts to improve requirements quality.

#2. Taxonomy of Quality Factors

A central repository of quality factors can help organize and clarify the existing knowledge in the field. This taxonomy should detail the various quality factors along with their definitions and examples.

#3. Taxonomy of Impacts

Researchers should work on developing a comprehensive taxonomy of impacts, detailing how quality factors affect different activities. This can provide a clearer understanding of the relationships between requirements quality and their practical implications.

#4. Context Factors

It is essential to explore context factors that influence how requirements quality is perceived. Recognizing the affect of elements like organizational culture, team dynamics, and tool usage can enrich the understanding of requirements quality.

#5. Economic Impact

Integrating economic considerations into the analysis of requirements quality will provide insight into the cost implications of quality factors. Understanding the financial impact of requirements can help justify quality assurance efforts in practice.

#6. Tool Support

Developing tools that apply the RQT to real-world scenarios can facilitate the implementation of quality assurance methods. These tools can help assess the impact of requirements quality on activities and support continuous improvement.

#Conclusion

In summary, achieving high-quality requirements is vital for successful software development. However, the current state of research in requirements quality lacks clarity and practical relevance. By introducing the harmonized requirements quality theory, we provide a framework that connects quality factors to their impact on software activities.

The ongoing survey of literature has highlighted the need for researchers to focus more on activity-based perspectives in requirements quality. By following the proposed roadmap, the field can advance towards more relevant and practical contributions that benefit both researchers and industry practitioners.

We invite scholars and practitioners to engage with the harmonized requirements quality theory and contribute to the discourse in the field. Together, we can enhance our understanding of requirements quality and its implications for successful software development.