Most start-up or existing businesses will need a business plan to submit to the bank if they are applying for bank facilities. The purpose of the business plan is to see if the idea can be profitable but it also allows a bank or any other lending provider to understand your idea and how the business will shape itself.
Business plans need to be clear but should explain:
The line of work you are going to be in
The profitability of the business
Where you will fit in this marketplace
What the goals and objectives of the business will be
What your unique selling points are
A sales forecast that will show that the idea can become an interesting prospect