Many years ago a teacher told me "A bad pencil is better than a good memory any day." I have found that he was absolutely right!
This past week I was making an entry into my darkroom logbook and noticed Volume 1 sitting there. The first entry is dated April 15, 1994. That was the year I moved to California and had just got my West Coast darkroom up and running; that entry captures details about what worked well and what didn't in the new darkroom.
Twenty years later I am still at it and up to Volume 6. Every print I make, every solution I prepare, and every problem overcome in the darkroom I record in the logbook. I do the same thing in the field with my camera, documenting how I structured the image and how to control it in the darkroom to create what I visualized at that moment.
Sadly, the whole art of note taking seems to be fading. That is sad. We're in too big a hurry. Maybe we don't understand the value of taking notes.
But I am a firm believer that if you really want to get good at something, you need to record what you are doing. Getting good (and getting better) in photography is no different. Writing it down helps you clarify your thoughts, helps you remember the details later, and compels you to pay attention to what you are doing.
I know people who keep a journal every day - and they can't image a day without it. I feel the same way about photography and my logbooks.