Bugzilla is an online software bug reporting system. It is widely used by both open-source software projects and commercial software companies and has become a major source to study software evolution, software project management, and software quality control. In some research studies, the number of bug reports has been used as an indicator of software quality. This paper examines this representation. We investigate whether the number of bug reports of a specific version of a software product is correlated with its quality. Our study is performed on six branches of three open-source software systems. Our results do not support using the number of bug reports as a quality indicator of a specific version of an evolving software product. Instead, the study reveals that the number of bug reports is in some ways correlated with the time duration between product releases. Finally, the paper suggests using accumulated bug reports as a means to represent the quality of a software branch
