It may seem like pointless info to write down until you have many years worth of local data to compare long-term weather changes and such to. You can learn a lot about what did and what didn't work in your area over the years. Warren Womack kept scrupulous records and his journals became a wealth of knowledge on southern archery hunting he has shared on a great podcast - give it a listen!
https://deerassociation.com/warren-womack/
I am keeping a journal of all my pig hunting on Oahu as it's been very difficult to catch up to them with a longbow, and I am trying to look for patterns and learn from my mistakes. I just keep a word doc. that I add to when I remember. I think it is very important to add what didn't work as well as what did.
Another version of this that a lot of people do is keep a camp journal in a deer camp. They are filled with as many good memories as they are good hunting advice.