I enjoy writing with a nice fountain pen on good quality paper and I use a notebook to record notes and basic diagrams during the day. I’ll type or dictate, of course, where a detailed and/or searchable record is required.
For some of the handwritten notes it’s not worth the time or the effort to transcribe into a digital searchable format but I still want to have some kind of index so that I can find something if needs be. As part of my end of day review I create a Note for that day (i.e. using the Notes App) and record a few key words.
Periodically, I’ll scan my completed handwritten notebook to PDF with my ScanSnap S1300i, usually a month’s worth at a time and, when backups have been made, I’ll destroy the paper. If I subsequently want to remind myself of something I wrote, I’ll search the Notes App for a keyword. This will show the Note for a particular day. I’ll then go the appropriate month’s PDF and scroll to the page(s) for that day.
So, my handwriting doesn’t deteriorate and I don’t have the frustration of flicking through notebooks multiple times before I find something.