What you intend to do with your notes is the thing that motivates you to take notes in the first place. The act of taking notes can be enough when getting started, there needs to be something more to keep going year after year.
Sometimes I struggle with motivation to write notes. It takes effort. The gratification is delayed. It’s not that I don’t find it valuable (writing is enormously valuable), but that I can lose sight of why I do it in the first place.
The best way to remind myself of why I should take notes is by producing works using my notes. For example, writing an essay or a brief from notes surprisingly fast (maybe I shouldn’t be surprised at this point) and reveals new ideas and questions to explore. My notes are a treasure map with caches stashed all along the digital garden.