This essay by Andy Hawthorne serves as a poignant manifesto for blogging:

There is a hidden value in blogging. There’s an old Zen saying: “Chop wood, carry water.” You do it not for the applause but because it needs doing.

Blogging forces clarity. It makes you structure your thoughts, sharpen your perspective. You stop writing fluff because — let’s be honest — you’re writing for yourself. And if you can’t keep yourself interested, nobody else stands a chance.

Short, pithy, beautiful. The Hacker News thread I got it from is a nice addendum.

Had to also add this extra reflective comment from @h14h on the same thread:

Blogging also creates something that never existed, and likely never would have existed.

If you believe consciousness is a way for the universe to know itself, then expressing your truth in a blog is a way to participate in that process. The random assortment of atoms that make up “you” are gifting the universe a novel creation that could not have existed otherwise.

Wow. This warmed my heart.