And from the comments:
> From my experience in social science, including some experience in managment studies specifically, researchers regularly belief things – and will even give policy advice based on those beliefs – that have not even been seriously tested, or have straight up been refuted.
Sometimes people use fewer than one non replicatable studies. They invent studies and use that! An example is the "Harvard Goal Study" that is often trotted out at self-review time at companies. The supposed study suggests that people who write down their goals are more likely to achieve them than people who do not. However, Harvard itself cannot find such a study existing: