Given the vast and growing number of open-source projects, one would assume its quality had gone down as quantity went up. In fact, the inverse is true, suggests a new report from Coverity, which spent the past three years analyzing more than 11 billion lines lines of code from 280 open-source projects. This is crucial given open source's increased importance to the software industry as a whole, and not merely self-styled "open-source companies."
Among other findings, Coverity's report reveals a 16-percent reduction in static analysis defect density. While Coverity's analysis doesn't cover all or even most open-source projects, which number in the hundreds of thousands, it does tell us a great deal about the quality of the more successful projects like Linux, Firefox, Samba, and PHP.
An open-source project will only be as good as the developers who work on it, but those developers have a strong motivation to make the code secure, robust, and high performance. The code is "naked," as it were. The source code is open. Customers and competitors are noticing.