I decline authorship quite frequently on papers. I love to help people out with their methods and am happy to review manuscripts but if I haven’t made a more significant contribution than that, I ask to be taken off or put in the acknowledgements.
I do still really appreciate it when people offer authorship. I recognize that our current authorship system is massively flawed and that it’s the only way these authors feel they can properly compensate me for the time I spend helping them improve certain aspects of their projects. What I wish for is that the system will change somehow in a way that will recognize the effort someone like me has on a paper. Because I’d like to do it even more. Often sitting down with a researcher for just an hour I can help identify important ways they can improve their paper methodologically. But I have no motivation to do so other that I like helping to improve the quality of research that is published.
I also that when it comes to grant applications or promotion committees, I am probably being compared to people who not might be so quick to remove themselves from authorship (and I suppose also people who have an even more stringent interpretation of authorship). I think behaving ethically with regards to authorship can have an important negative impact on a researcher’s career.
And I don’t think people are bad in accepting to be authors on papers which, technically, they don’t actually qualify as authors. We’re all human and if you give us bad incentives or a system that doesn’t allow to recognize people’s efforts except through authorship, it’s entirely expected that we will accept this type of authorship. As I’ve mentioned before, we need to revamp the authorship system and be more specific about what we’re giving people authorship for. If someone was involved in data collection, make them a “data collection” author. If they provided important feedback on the manuscript, make them that kind of author. Let’s maintain “main” authorship for the people who are really behind the project. The people without whom the paper would not exist.
