Another case in favor of FLOSS, is the how software can be developed. FLOSS gives a lot of flexibility, since development is not centralized it allows for software to grow more organically.
There is a more symbiotic relationship between the software and the community that grows around it, meaning that the software grows as it's community grows. Which is a great thing to have, since it means that the software is less dependent on a small core of developers. As such, the odds of it going under are a lot less than closes source projects.
The freedoms that FLOSS gives, mainly that you can study and modify the software, means that projects can be forked to better suit needs that the original development team can't, or doesn't have the intention, support. This aspect give FLOSS a lot more flexibility to better cope with the needs of users, by being able to be adapted to new environments, or just the changing needs of users.
Being able to adapt, or if needed fork, projects to better suit user need can be a lot faster. It comes to down to communities to adapt software for their purposes if the core development team doesn't do so. Forking a project can be an option, a powerful one, if there is a need to do so.
In many respects, this level of flexibility makes FLOSS a powerful for people. Specially because it empowers people, by giving us the tools to be able to build the software we need when we need it. There is no single centralized core to tell people how certain software should work, yet several nodes of people joining forces to implement the best way to do what they need to do.
It's a pairing of what people needs, with the tool they need to do the job done.