I do this basically any time I feel like my short-term memory is overwhelmed with facts, and as a result the notebook has effectively become NVRAM for my brain.
"Hold on a sec, I just wanna write down what I was doing so I don't lose my place."
If you want to add more, after writing it down, you can follow up with, "sorry to keep you waiting, but when I get interrupted I often forget some useful details about what I was working on, and I want to get that down before it leaves my head".
(The "when I get interrupted" is a bit of a cheeky way to point out "you are imposing on me, so the least you can do is allow me this".)
I store all my org files in git repositories and sync them across devices, allowing me to work on multiple devices and worry less about losing a particular device.
Items don't have to be tasks. They can be ideas or general notes.
The "today" section is a bulleted list of the things I think I'm working on today. I add to it through the day as I get shoulder-tapped, or as I realize another important sub-task.
As I finish tasks, or at the end of the day, I move them up into the "history" section under the current date. Thursday: A, B, C
This is basically all of the "head state" in the infamous cartoon of how you ruin engineers lives by interrupting them. I feel that it allows me to be interrupted without losing import state, and it's also a ready-made "scrum status" of what I did yesterday, and an augment to my memory when someone asks me "did you change X?" for some micro-task that was too small to ticket.
I feel this has helped me be a more effective developer, in spite of my decaying memory, than I was when I tried to keep everything in my head. :)
Example contents: https://imgur.com/a/VI64Jx6