A brief account of how the company began- You should mention in your business plan the history behind the formation of you company and the background of the founders and directors.
An exit strategy- A business plan becomes perfect only when you write a good exit strategy for the investor. It is important to note that investors generally have a 3 year horizon within which they want to exit. The author is the partner at IntelligentQ. IntelligentQ specializes in Integrated Marketing Communications: Business Content, Sports Content, Business Plans.
A business plan should be detailed. In listing your products and services for example, you should not really stop by just enumerating them. You also should write down the descriptions and scope of your products and services, touch base on production and identify means on how you can market your "brain - child" to your targeted niche.
Attention to detail. A plan that is concise and clear reads professionally so don't make yours too wordy. The reader needs enough detail and information to be able to make an informed decision. As with all professional documents, care must be taken to avoid spelling mistakes and use correct grammar and punctuation. A plan that makes absurd or unrealistic assumptions is of no use so stick to the facts and make sure you are making credible projections and accurate content at all times.