A small business owner prepares a marketing plan to identify his target customers, the strategies he intends to use to reach them and the resources required to implement the strategies. The marketing plan must be well researched and carefully thought out. Weaknesses in the marketing plan invariably lead to disappointing actual sales results.

Failure to Demonstrate Customer Need

To succeed in the competitive marketplace, a business owner must offer products and services that customers have a strong, immediate need for. The marketing plan should clearly express the compelling reasons that customers will view these products and services as something they are convinced they must have -- a top purchasing priority for them. In a weak plan, the products might appear as merely nice things to have.

Incomplete Analysis of Competition

A glaring weakness of many marketing plans is not showing the strengths and weaknesses of competitors and comparing them to the strengths and weaknesses of the company. The business owner may not have taken the time to gather this information before creating her marketing plan. An understanding of the competition is critical because a business owner devises her strategies to take advantage of any weaknesses she uncovers about her competitors. She also tries to showcase her company's strengths versus the competitors in all communications she has with potential customers.

Market Size Overstated

Small businesses often believe their market is larger than it actually is. A tennis training facility owner for example would be incorrect to obtain figures on how many tennis players there are in his metropolitan area and use that as his market size. Not every tennis enthusiast would be willing drive across town to improve her tennis game -- particularly if there are other practice facilities nearer to her home. A better approach is to determine through surveying potential customers how far they would be willing to drive. The important number in the marketing plan is the addressable market -- how many customers you can actually reach. He may find out his actual market is tennis players within a 5 mile radius.

Lack of Detail About Implementation

Marketing strategies explain what the business owner intends to do to grow her company, such as expanding her market from the West Coast to the Southwest. Marketing tactics show, step-by-step, what needs to be done to implement these strategies. Weak marketing plans often have bold, visionary strategies but no real explanation of the numerous tasks required to accomplish them -- or whether the company has the necessary human resources, skills and financial resources to complete the tasks.

Underestimating Marketing Cost

Many early stage companies find out that the cost of entering the market is much higher than anticipated -- and sales build more slowly than the business owner hoped. Established companies that are expanding into new markets may also find that they underestimated the expenditures required to gain exposure for their products and build a customer base. One approach to remedy this is to include extra funds in the expense projections in the marketing plan, sometimes called contingency funds.

Unrealistic Sales Projections

Entrepreneurs are by nature optimistic, but this optimism should not be translated into outlandish sales projections. A frequently seen error is saying, for example, that the total market size is $1 billion, and therefore the company only needs a 5 percent market share to be a $50 million enterprise. The business owner fails to recognize how many individual customers must be acquired to reach this lofty sales number, and how difficult it will be to reach them and convince them to purchase from the company.