Open Science is the practice of science in such a way that others can collaborate and contribute, where research data, lab notes and other research processes are freely available, under terms that enable reuse, redistribution and reproduction of the research and its underlying data and methods.(Source: FOSTER)
You have learned that good data management contributes to the findability, accessibility, interoperability and reusability of your research data. This does not necessarily mean that you should make your data openly available. But to open up data, you do need good data management from the earliest possible stage of your research project.