I was asked recently why I blog. It sprung up out of my livejournal days, when I found that putting things in writing gave them a permanence, and helps to hold me accountable. Plenty of people have written about the importance of writing down your goals and the benefits of it. What I don't see often written about is the joy I get in going back and rereading my own posts. Seeing how much I have changed, survived, messed up and kept going anyway, and my ability to laugh at myself, shows a strength that I often forget I possess.
The final reason is the advice and feedback I get from readers, or when you reach out for help is wonderful, and that too keeps me moving forward as a person, so I can keep evolving.