I say that because of course you need to be careful with commercially sensitive ideas, as you do not want to pass your plan on to someone in the pub who then starts your idea before you across the road.
Everything on earth is tending to become compact. Gone are those days when a sea beach was described in a thousand words. Today, a similar description is possible with a powerful visual and a string of strong adjectives in only a few words.
Most of all if you are seeking funding for your business, it will be absolutely crucial to go along and show someone an actual plan, because there will be very few people who will loan you money on the basis of what's just in your head. So it's pivotal to have a plan and be committed to preparing that document.
Describe the manufacturing or operating process and associated costs. Contain believable finical projections, with key data explained and documented.