It seems to have been put there to fill the need to attribute a certain sum to marketing. Make sure you are researching each point of your budget, make sure that you are giving it context and it makes proper sense within your overall plan.
I teach that you should seek to learn from competitors; obviously never copy another business's idea or what they are doing, but you can absolutely learn from their mistakes or see what they are doing and discover ways to improve it. All of that analysis belongs in your business plan: make sure you have your competitors under the microscope and make sure that is a solid chunk of your plan. That is some of the best research and information you will gather about what will make your business successful in future.
The business plan serves several purposes: Enables the entrepreneur to think through the business in a logical and structured way and to set out the stage in the achievement of the business objectives ; Enables the entrepreneur to plot progress against the plan ; Ensures that the resources needed to carry out the strategy and the times when they are required are both identified ; Preparing the business plan ensures that the entrepreneur has thought through the crucial aspects of the venture ; It is a means for making all employees aware of the business direction ; It is an important document for discussion with prospective investors and lenders of finance ; It links into the derailed, short-term, one-year budget.
Production/ Operation plan: The production/ Operation plan should include strategies for the following parameters ; Location and reasons for selecting the location ; Physical layout ; Cost and availability of machinery, equipments, raw material ; List of suppliers and, if possible, distributors ; Cost of manufacturing ; Quality management ; Production scheduling, capacity management and inventory management ; Changes in above in the case of expansion of business.