Some effects of open-source softwarre on the quality of software products are:
Reliability: Generally open source softwares not rely on any other payable softwares, so if we use such software
Products for out projects, it will help us to improve those libraries well and easy since they are open source.
Stability: As these are open sources, any one can able to modify code to bring stability.
Audibility: Means tracking made easy, since they give most flexibility.
Cost: They are cost free, so we can use more number of softwares that increases quality.
Flexibility and Freedom: Any one can modify, there are no constraints on source code, source code is free for use..
Support : Supports more number of functionality and freedom to distribute.