F.A.Q
Convincing an organization's management that in this kind of infrastructure- building, long-term effort is a good investment is often difficult. Given the amount of time that goes into frameworks, many organizations simply do not have the resources to create them, irrespective of how convinced they may be of their advantages.
Because frameworks tend to be large and fairly complex pieces of software, they are often not a cost-effective project for a single organization. It is also a good thing when a particular framework is used in many projects - it grows, it becomes a de facto standard to a degree, and the organizations using it get the benefits. All of these factors mean that frameworks are good candidates for open-source projects, and indeed many of the best frameworks are open source.
The secret of open source is knowing what to use and when. Many criteria help in choosing an OSS project: license, support availability, user base size, community, and suitability to the task.
Why would a developer or company release a framework as open source anyway? What could be the motivation for such an action? An application framework is a major development effort for any individual or group. Why write it and then give it away? Actually, there are some very good reasons, all of which are quite practical.