You can concentrate so much on essential financials and supply logistics, but overlook other issues like marketing or opening times. By showing the plan to someone you trust, they can have a look and see what might be missing or worth developing more. Getting that valuable second opinion on how robust your idea is will put you in a much better position to start and keep going successfully.
Drawing functional Plan: After positive result form the feasibility study, functional plans are drawn up. Some scholars and writers prefer to include feasibility study with functional plan but the two have been taken separately. Whereas only after the feasibility study can one go into the derails of drawing up functional plans which would determine the strategies for all the operational areas : marketing, Finance and production.
It is outline of the business giving details of the finance, assets, staff, products or services and markets. It guides the entrepreneur, it identifies possible problems and it is also used in funding applications. The business plans sets out how to owner of a business intends to realize its objectives.
So it is crucial that every time you mention financials in your business plan, to really give them the correct context. When I have worked with clients in developing business plans, there has been a budget or amount set aside for example to be spent on marketing, which has been decided a bit arbitrarily. I mean with no real research, no understanding of what that amount needs to be spent on, and what that budget will truly achieve.