From Cory Doctorow:
The very act of recording your actions and impressions is itself powerfully mnemonic, fixing the moment more durably in your memory so that it’s easier to recall in future, even if you never consult your notes.
The genius of the blog was not in the note-taking, it was in the publishing. The act of making your log-file public requires a rigor that keeping personal notes does not. Writing for a notional audience — particularly an audience of strangers — demands a comprehensive account that I rarely muster when I’m taking notes for myself. I am much better at kidding myself my ability to interpret my notes at a later date than I am at convincing myself that anyone else will be able to make heads or tails of them.
Writing for an audience keeps me honest.
[…]
These repeated acts of public description adds each idea to a supersaturated, subconscious solution of fragmentary elements that have the potential to become something bigger. Every now and again, a few of these fragments will stick to each other and nucleate, crystallizing a substantial, synthetic analysis out of all of those bits and pieces I’ve salted into that solution of potential sources of inspiration.