I have logged everything and it's a great resource and priceless keepsake.
I dive configurations from swim trunks to cold water drysuit and with many different cylinders. Being able to go back for weighting and configuration variables is very, very helpful.
Being able to relive dive outings from my notes, who, what, where, dining after, you name it is fun now and wlil be priceless if I ever need to hang up my fins.
I can go back and cite multiple water temperatures when we talk about global warming.
I have all of the information to tally my SAC if I want to monitor or track it.
I tally lifetime and year to date dive counts.
I used to use a spreadsheet in Excel. Lately I use a 3X3 post it note per dive, I have arrived at a shorthand for a lot of it, 6 to a page in page protectors to note it all. it's all in a zip-up binder along with other reference materials. The downside to paper it that it is harder to back-up. I have avoided dive computer programs as a long term record sine many rely on unique applications for access and those will eventually be unsupported files. I suppose one could print those records or export PDF files but that seems low density if you desire carrying hard copy along.
For odd activities, like pool dives I still log the event, I just don't increment the count. Odds are I was testing something and wand a record of it. It's your log make it serve your needs.
Pete