And I usually give the generic answer of "it gives me a place to put down my thoughts" or "to keep in touch with people" or "to help me remember when something occurred."
All of which are mostly true, but I think it's more because I amuse myself to no end.
No, it's true. I'll go back and read entries from weeks or months ago, and laugh at my own jokes. I personally find myself hilarious and often I try to put some of that hilarity into my journal not just so that my readers can enjoy it (because I honestly don't believe many people actually read this), but so that I can enjoy it.
Oh, it's true. Case in point: I was reading back my last 25 posts and came across this one. Seriously? I laughed out loud at the first part. In my room, by myself, reading my own words, and laughing out loud. (It was the clever and poignant use of "jerks" that did it.)
Clearly, I'm a winner.