Sharing data at the end of a project makes it available for reuse by others. This is increasingly being encouraged by both funders and the research community more generally: it is very rare for the full potential of a research data set to be fully mined in one project, and sharing helps maximise the value of the data.
While not all data is suitable for sharing, the general trend is towards openness as the default, with restrictions only as necessitated by specific legal, ethical, or commercial considerations.
These benefits may also make research projects which plan to share their data more attractive to funding bodies, resulting in another potential benefit to researchers who opt to do this.
Researchers are sometimes concerned that their data will be misused, or that it will be used only to question the original analysis. However, in practice, this is rare. Researchers can reduce the risk of misinterpretation of their work by ensuring that data is well documented, and including clear methods information helps make it straightforward for other researchers to validate their conclusions. But shared data is also frequently used in ways not envisaged by the data creator: the focus may be on variables or aspects of the dataset deemed unimportant for the original project, for example, or the data may turn out to be valuable to researchers in another discipline, or may provide inspiration in terms of content or methodology.
Source: Research Data Oxford