* Earlier Defect Detection: Inspections, often involving walkthroughs or formal reviews, occur *before* the code is even compiled or executed. This allows for the detection of defects at much earlier stages of the software development lifecycle (SDLC), making them significantly cheaper to fix. Testing only finds defects *after* the code is built.
* Finding Different Types of Defects: Inspections are more effective at finding high-level design flaws, architectural weaknesses, inconsistencies in requirements, and missing functionality, which are often missed by testing. Testing primarily focuses on functional and non-functional aspects like performance and security once the code exists.
* Improved Code Understandability and Maintainability: The process of reviewing code together in an inspection improves overall code quality by fostering shared understanding and encouraging adherence to coding standards. This leads to cleaner, more maintainable code in the long run. Testing doesn't inherently improve code understandability.
* Knowledge Transfer and Team Building: Inspections provide a valuable opportunity for knowledge sharing and team collaboration. Less experienced developers can learn from more experienced ones during the review process.
* Reduced Debugging Time: By finding defects early, inspections drastically reduce the amount of time spent debugging later on. Debugging after code is built and tested can be much more complex and time-consuming.
* Cost-Effectiveness (for certain defect types): Fixing a defect during an inspection is considerably cheaper than fixing it during testing or after deployment. The cost savings are most significant for high-level design or architectural flaws.
However, it's crucial to understand that inspections are *not* a replacement for testing. Inspections are excellent at finding certain types of defects but cannot identify all possible runtime errors, performance bottlenecks, or subtle interactions between code components. Testing is essential to verify the actual behavior of the software. Ideally, a robust software quality assurance process incorporates *both* inspections and testing.