Did you ever stop and think what a unique position you're in as a business owner? I don't know of any other way you can have as much control over your success than owning a business. When you work for someone else, you are totally at their mercy as to what your future may be like. It doesn't matter whether it is a private business you work for or a large corporation. Your future is in their hands. The only thing that might qualify other than owning a business would be to inherit or win a lot of money that would give you everything you want in life. So, why make a business plan the normal way when you could first make one that could give you what you want in life? Have you ever thought about doing a plan like that? Would you know how? Would you have the time to do it?
When you, and your partners if any, have all the core skills and industry knowledge you need to start right away without seeking experts, napkin notes may be enough to get going. Let's say you are already an expert in technology and social media. Then you, and your team, probably don't need a detailed plan to start developing a new app. You will draw on your knowledge and experience, and you understand that you might need to go back and do some more detailed and formal planning later. Certainly when you reach the point where you are looking for investors or lenders, you will move beyond those first casual notes. Until then, drawing upon your expertise can allow you to quickly jump into the market and perhaps gain a competitive edge by using a minimalist plan.