For me, one of the most annoying things that happened to me since I started using open source software on the regular basis is receiving criticism from people that haven't used it, or ready understand what's it about.
Using open source, for me, is about having access software that gives me the control on how it works. And it's also about the philosophy, and principles, that the open source community brings to the table.
People coming to collaborate in projects, in a open way is the way to move forward and it's in the best interest of the community at large.
In the short, and long, runs collaborating this way offer the best way to do things in all the fields. Since all happens on the open, we all can see how things are done and the individual is free to participate in the way, shape, or form that fits his or her personal interests.
Collaboration in an open way can speed things up, since the ideas and information used in the project can be shared with the most people possible. This means that solutions can be found a lot faster, and new ways to use the information and the ideas can be found with a lot more ease.
Another one, is that is harder to use the projects in a way that can be harmful. Since there are a lot of eyes looking at every aspect of each project done this way, it's a lot harder to put in anything that can be detrimental to the project, and it also means that it can be fixed a lot faster if somethings does go through.
It also means, that parts of existing projects can be used to create new projects, or enhance current projects. And since the projects are open, any one can see from where, by who, and when any particular piece of the project was pulled. Or, if it was a new piece created specifically from the project at hand.
Collaboration between individuals, and groups, in an open way should not only be allowed to do so, it should be encouraged.
The pros of doing things in an open way to the community at large, vastly outweigh any cons that could come from it. Information and ideas, are the building blocks of knowledge. We all have the right to access knowledge without any impediment.
Knowledge can not be allowed in ownership of any particular individual, or group. Knowledge is only valuable when it can freely flow among the societies and communities at large. It needs to be shared and used freely by anyone who's interested, or has a use, for any particular knowledge.
At the end information, ideas, and knowledge is a commodity that belongs to everyone.