In regards to functional uses, what have you found does NOT work for you?

Question in title! It doesn't matter what specific purpose (outside of journaling/diary writing) it is/was for, what have you learned along the way does NOT work for you or help you or what do you simply can't be bothered to keep up with?

For me: This year is the first one I'm using a weeks (have since last November) and I wanted it to be mostly for college & general planning & maybe some health tracking. I'm still figuring it out, but I originally wanted to hsve one column where I jot down what (topic wise, specific exercises/cases, etc) I worked on that day. Now, I also wanted to track how much time I spend on uni per day, so i got an app to track that meticulously. I realised that since I'm putting in what I'm doing during the recorded time in the app I hust feel like what I'm putting into the weeks is either less precise or just redundant since I have that info elsewhere. I also use a weekly master list on the blank pages so putting in specific daily tasks that double those on the master list or assign them to certain dates feels a bit awkward and I'm still figuring that out too.

Last year I also used one column in the monthly things from my A6 (where I habit track) to note down days where there's official holidays or officially no lectures. I felt that that was a bit unfitting and unnecessary, so for this year I marked all those (and other uni related) dates on those box calendars on the very first page and I like that a lot better for an overview.

Would love to hear what your guys' journey with figuring out what works and what doesn't has been like!!