Most notes I don't need to look at ever again after they've served their purpose, be it a month or three minutes of use. For the ones that do, I will use my notes to write a digital writeup, usually with more detail and references throughout with the explicit intention of making it comprehensive for when I forget everything in 6 months. I find the process gives me all the benefit of paper and all the benefits of digital, but supercharged because I am recalling from a written note at the same time to synthesize these ideas into a new format.