I think that in the article The Memex Method Cory Doctorow provides an explanation that I could use for why I blog. While when I write something here in a manner that is legible to anyone, I know that my real “audience” is myself. The most useful feature is the On This Day link above that collects and displays prior years entries on this site, which I look at each day to recollect what was meaningful to me in past years.
My writing since 1999 has accessible on the web, although not all in one spot, which may be a mistake on my part.