I love journals. I've kept one on and off all my life. I used to be so specific about what could and couldn't go in a journal though. No lists, doodles, plans, school work, notes, etc. etc. This was a book about the days of my often boring life. It must be done right.
For this reason, I would abandon "imperfect" journals half way through and start a new one. The possibility of making a fresh start was uplifting. Besides, everyone who becomes famous wishes they had journaled in the past so they could sell the dang thing for millions.
I was a kid. My stupidity was cute back then. But I still keep two separate books, one as my journal and one for anything else.
I journal for a lot of reasons. I think best on paper. The words just come easiest that way. It gets things outside of me too. I don't have to carry it around so much anymore, because I processed it though words. I can't just make those words come out of my mouth. My mind goes blank and I look and feel about as intelligent as drowning goldfish.
Journaling also helps me process incomplete thoughts. It gives me time to further explore certain things and see then through. For some reason, I am incapable of doing this in my head. I suppose rather than dwelling on my glaring inadequacies, I should just be grateful that I have a way of doing so at all, even if it is not particularly efficient.
I've completed four journals in the past few years. I'm actually forever grateful for the habit, as I have a tendency to forget a lot of things. I love going back and rereading what I wrote, rethinking what I thought, revisiting the past. Personal history. Words are always there for me, even when my memory is not.
To some people, keeping a journal is like a burden. Something on their "to do" list. These people are mostly 'trial' journalers, in my opinion because few of us stick with things we don't like when we don't strictly have to do them. Which is why most of us go to work but not all of us journal. All of us shouldn't journal anyway. You should journal is if it is useful to you. Other wise, save a tree and your sanity.
But for me, a journal is a release and a joy. It is a very private thing, I'd really rather other people didn't read it. Because it's just for me. Most of it is worthless worries, thoughts, or other forms of expression. Yet it is helpful to me in some way, this thinking on paper.
I often think thoughts I didn't know I was thinking at all.