Why the product specification is usually the largest source of bugs in a software product?

The product specification is often the largest source of bugs in a software product because it serves as the foundational blueprint for development. If the specifications are unclear, incomplete, or ambiguous, developers may misinterpret requirements, leading to discrepancies between the intended functionality and the final product. Additionally, changes to requirements during the development process can introduce inconsistencies that further exacerbate the risk of bugs. This misalignment between expectations and implementation is a common source of defects in software.