I keep my cars til they're ready for the scrap heap - anything "major" like spark plugs etc I'll write on the air cleaner box, oil changes are kept track of using the sticker on the windshield.
Even when selling a car I've never had anyone ask for maintenance history.
I get the point of keeping records, but some people hilariously over-do it, no point in writing when you bought wiper blades or put a plug in your 7 year old tire , or bought a touch up pen for the 2 inch scratch on the lf fender (yes I've seen that in someones log book)