Investigating the Relationship Between Code Quality Metrics and Software Maintainability: An Empirical Study

Software maintainability is an important aspect of software quality because software systems require regular updates, corrections, and improvements throughout their life cycle. Poorly organized source code can make it difficult for developers to identify and fix errors, modify existing functions, perform testing, and introduce new features. Therefore, understanding how code quality characteristics relate to maintainability is essential for developing software that can be maintained efficiently over time. This study investigates the relationship between software maintainability and selected code quality metrics, including Lines of Code (LOC), Cyclomatic Complexity, Code Duplication, Coupling, Code Smells, and the Maintainability Index (MI). Each metric represents a different aspect of source code and provides information that can help identify potential maintenance challenges. By examining these characteristics, the study aims to understand how different code properties are associated with the ease of maintaining software systems.               The study recognizes that software maintainability cannot be fully evaluated through a single code quality metric. Cyclomatic Complexity, code duplication, and coupling can help identify structural characteristics that may increase maintenance effort, while code smells can highlight areas requiring further investigation. The Maintainability Index provides a combined estimate based on selected code characteristics, although its effectiveness depends on the calculation method and the factors included. Considering these metrics together can provide a broader understanding of software maintainability and support more informed decisions about code quality improvement.

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