Marketing Plan: Marketing plan lays down the strategies of marketing which can lead to the success of business. These strategies are in terms of marketing mix (product, price, place and promotion). From the market feasibility study and marketing research, potential/ present demands of customers are determined which helps in understanding the profile of customers and hence help in laying down the strategies for segmentation of the market, identification of the target market laying down strategies for target market.
It could be, for example, the risk of a change in the economic environment - what are your contingency plans for that in terms of dealing with such a situation? There may be many other risks as well specific to your particular sphere of operation, but that ability to plan ahead for all scenarios makes for a robust business plan.
The reality is no matter how much you work with things in your head, no matter how confident you may be and how much you think you already have a great vision for your business, there are so many great reasons why you should get it down on paper.
Business planning process : As discussed above, a successful entrepreneur lays down a step by step plan that he/she follows while starting a new business. This business plans acts as a guiding tool to the entrepreneur and is dynamic in nature - and needs continuous review and updating so that the plan remains viable even in the changing business situations.