Objectively speaking, the research of the National Natural Science Foundation mainly reflects the level of theoretical research, because you can only use high-grade papers as the research basis and do not need related actual products or projects. In addition, as long as you publish a high-level paper, you can complete the topic without completing the actual project. But subjectively, project approval often depends on judges at all levels, with a subjective component of 10%-60%. A responsible high-level judge may only have a subjective component of 10%, while an irresponsible low-level judge may have a subjective component of 60 or even higher. In addition, your application is well written, and you may encounter unfamiliar judges who are not optimistic about your project. So the lucky question of applying for the National Natural Science Foundation is to see what judges you will meet. To sum up, NSFC projects can only reflect a person's theoretical level to a great extent, but not the actual level of product innovation and research and development.