I've tracked every book I read since 2015 when I did my first reading challenge. I started because I wanted to know how many "off-list" books I was reading that weren't part of the challenge.

I've continued because I like having that record to look back it. I can sort by rating to figure out what the best book I read that year was, or how many books I've read that I disliked that year, etc. And also I can remember if I actually read a book before vs just saw it in a store or it had a similar title to something I read.

I started on Goodreads but this year I'm using storygraph too and might switch over entirely; I like the additional stats and the ability to give partial stars.