would love to know why too! personally i highlight and annotate my books (current read is The Trouble With Being Born by E.M. Cioran) bc if i were to re-read, i also would get to re-read how i felt as well as what made me feel the way i did... it's like self-induced nostalgia for whatever memories and emotions i had from when i first read and annotated my books <3 thats also why i date when i start and finish my books on the first and last pages too! it's like a little archive of my emotions and lessons i learned from each lil book (: we have so much at our fingertips for documenting, preserving the physical self (photos, video, embalming, etc) but seldom do we ever archive how we felt in these memories (besides diaries and journals ofc), so i guess i wanted a way where i could pickle my thoughts and let them marinate that wasn't just journaling :P