Why choosing open source software instead of a "closed" package of a traditional software supplier?

1. Independence of software suppliers: You are no longer bound to one single software supplier having the property rights.
2. Openness and security: You are able to verify, whether the software delivers what it promises, yourself, or by a third party.
3. Reuse of knowledge and software components: closed source software tends to reinvent the weel over and over again. Open source software grows organically; bad ideas extinguish whereas good ideas develop and are being reused in other projects.
4. Open standards: The concepts in an open source project are being developed by many developers and organizations all over the world. Through this huge basis many of these concepts grow into international accepted open standards. This results into better inter-operability.
5. Open source development enhances quality: quality refinement takes place by all participants in open source projects. This can add up to hundreds or thousands of users and developers. In traditional closed source development this is solely done by the supplier itself. The supplier judges whether a certain functionality is essential and wether the quality of the software is satisfactory to deliver or update.
6. Fitting to certain user demands is less complex: Openness of the code always enables adjusting the software to existing systems, tools, platforms, databases et cetera.