1. Because memory is a slippery bugger.
When I was 31, I backpacked alone through Vietnam without a journal. I’d recently purchased a pricey camera, so I enthusiastically snapped hundreds of photos, never bothering to write down a word. Not surprisingly, what I retain from that trip are imprecise memories and a shoebox filled with slides of people and places I can no longer name. Furthermore, because I traveled solo, I can’t even poach my friends’ memories for missing details. In short, I didn’t bother asking myself what I’d want to remember and what I’d likely forget.