If you are to get the most benefit out of the planning process that leads to a written business plan, you have to be the most critical reader of the plan.
You know you have a good idea or you wouldn't even be thinking about writing a business plan. Therefore, you may have to force yourself to be skeptical and to challenge every assertion contained in the plan. If you're serious about succeeding, you have to make the planning process work for you by being completely realistic about your chances, and even to think about worst-case scenarios. The fact that you have a good idea doesn't necessarily mean that you have a profitable idea. The time to unearth all the potential pitfalls is in the planning stage, not later on when unexpected events tend to be unfavorable and costly.
There may be others within the business with whom you will share the business plan, or substantial pieces of it. Clearly, if you have partners, co-owners, or a Board of Directors, those individuals should see the plan after its completion. They may also have significant input into the plan as it's being developed.
If you have employees, many of the goals that you set for them will be derived from the plan. For example, your sales projections translate directly into the expectations you have regarding the level of sales your representatives must achieve. In general, your people will be able to do a better job if they see exactly where they fit in to your overall business objectives.
Obviously, there may be parts of the plan that you won't want to
share with your employees. This is particularly true of portions that
might reveal more than you want them to know about your personal
finances. Similarly, you may not choose to share information regarding
how the business finances its operations. You'll have to use your
judgment regarding the type and amount of detail that will be relevant
to each of your employees. In many cases, you may want to share with
them only your executive summary and the top-line goals for the year. In
other cases, greater detail will be necessary and helpful in motivating
key employees to "get with the plan."