I do because I want to modify the software to be useful for my use, to write software that I do not find an existing suitable one, and to make available to othe

I do because I want to modify the software to be useful for my use, to write software that I do not find an existing suitable one, and to make available to others who also might find this software useful (and that others can modify it if they need to do so, too). There are other benefits of FOSS, too. I will sometimes accept feature requests and bug reports, although there aren't many, since not many people use my software.