Have you ever written an important phone number on a napkin or the back of an envelope? On the one hand, you get the information scribbled down; on the other, that piece of paper is so insubstantial, it gets lost or trashed by you or someone else.
Laying out a quality plan with a definitive, thought-provoking end goal will yield a much better long-term result than a plan that only solves a temporary need.