The most important reason to write a business plan is probably to save your house, or grandma’s nest egg, or whatever investment you are putting at risk. A business plan will help you learn more about your business and serve as a tool for communicating with others, such as bankers or investors.

Here are seven things to know about business plans:

1. Most businesses are started without written plans. For the most part, plans only exist on a napkin or in the owner’s mind. Business planning is an unfamiliar trek for most people, and too often the task is avoided until they are urgently needed to get a loan.

2. By the time a business plan is printed, it is probably already out of date. Enterprises continually adapt to their surroundings and the plan is a living document that gets updated at strategic times.

3. Business planning is an organic, non-linear process. At any given time, you will be more knowledgeable in some areas than others. Effective business plans arise from building on strengths, developing strategies to mitigate weaknesses, and innovating as you learn more about your business.

4. The further a business plan projects into the future, the less reliable those projections will be. It’s entirely likely that year five predictions will be less accurate than year one.

5. A professionally prepared plan does not guarantee a business will succeed. A picture-perfect business plan is not worth the paper it’s written on unless the owner understands it thoroughly. The real value of a business plan is the knowledge you gain by doing it.

6. Plans that call for aggressive early stage spending will meet with resistance, especially where the shopping spree is predicated on using borrowed money. It’s usually healthier for a new business owner to solve problems through innovation, ingenuity and frugal investment of available resources.

7. While a business plan will help to increase your knowledge about your business, it will not do much toward helping you develop business trade skills, such as how to handle money, how to buy, sell and pay. Business trade skills are more likely to be learned from managing a paper route or operating a lemonade stand. Owning a business is the best way to learn the basic survival skills like knowing how to read the market, how to learn from it and how to change your mind.

Your business plan is more for you than it is for your banker. It will enable you to prove your business case, and to be reasonably sure that your venture can survive.

Once you’ve debunked your own assumptions and gathered enough evidence to demonstrate viability, you’ll have more confidence in your business idea. Armed with a better understanding of your business and realistic financial projections, you will be much better positioned to discuss your business with those who might help you.