It depends rather on what your aim is. Most projects are only interested in producing good software with a thriving community, and requiring copyright assignmen

It depends rather on what your aim is. Most projects are only interested in producing good software with a thriving community, and requiring copyright assignment or a CLA gets in the way of that. The FSF has another aim though, which is to uphold the free software movement in general and defend the validity of the GPL in particular -- so they have a copyright assignment policy for FSF projects like gcc which helps in achieving that. You might not care about that FSF goal, and the copyright assignment process is a definite barrier to new contributors, but there are reasons behind it and they're neither arcane nor stupid. Other kinds of contributor agreement I know less about, and some of them can be counterproductive or even one-sidedly in favour of the company, but in general they stem from the organisation having some extra aims or requirements beyond the pure desire to have a thriving project. "If in doubt, don't have a CLA or assignment process" is probably good advice though.