I'm involved in a long collaborative software development project. The project required continuous effort because the goal is very ambitious and the project started from scratch.
However, some early collaborators contributed to the projects very little, one was an undergraduate who didn't have the skills to contribute significantly to the project and the other was a post-doc who caused more harm before ultimately leaving the group.
My question is do these early collaborators deserve authorship on any publication that may arise from this project? If no, at what point would someones contribution constitute authorship?
Here are some thoughts:
Pro: They did technically contribute to an early prototype, and I wouldn't want to be left out of a paper that I contributed to, but couldn't ultimately see the end of because of other circumstances.
Con: The project has substantially changed since they contributed to the point and it's debatable it's even the same project anymore, as practically all the software has changed. More importantly to me, it dilutes the effort of the authors who contributed significantly more, and this can be discouraging.