Comment by SpaceNoodled

Agreed. Grabbing a pen and a post-it is faster for me than opening a text document, and a pad of paper allows me to format and diagram things freely.

The post-its can be sorted, stacked, moved, stuck to pertinent notebook pages, altered, and ultimately recycled when they are no longer relevant. It's much freer than a document on a phone or computer, where it can still be a pain to move information from one domain to another.