As a performance tool, it measures the progression of goals in one's business by tracking, monitoring, as well as evaluating, and can also be used as checkpoints in measuring performance. The world today, is so dynamic that what applied today might not apply tomorrow, and as a result of this dynamism, a good business plan needs to be setup in order to protect one against risks associated with business.
Far be it from me to dampen your enthusiasm, but you should give yourself every opportunity for success. That's what the planning part of the process of creating your business plan will do. By the time you have pressed your way through it, you will not merely have some neatly arranged document to keep on file, you will have a working tool that addresses the essential factors that influence your future.