Walk into any bank in the country and ask for a loan to start a business and the knee jerk reaction of the banker behind the desk will be to ask you to write a business plan—even though they themselves have likely never written one and will not base their lending decision on its content. The problem with writing a business plan as a start-up is that it will be based on one assumption on top of another. If your first assumption is flawed, then the whole thing is useless.
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When Writing a Business Plan Is a Waste of Time