The problem that I have with paper is refactoring.

Creating my todo list, investor update lists, company admin info, idea explorations, and everything else always involves me evolving the idea continuously and shifting things about as the structure changes.

With paper this means using an eraser until I end up with a crumpled mess, or laboriously rewriting it all over and over.

I like the tactile nature of paper, if only I could select chunks by dragging and erase (fully) without wrecking it.