Marketing Research will be the first component for your marketing plan. You may be doing this in house or you may elect to hire a top marketing agency, a marketing consultant, or maybe a specific marketing research firm. You need to obtain and capture all data about your business along with your products and services to help you properly facilitate any potential marketing problems. You may also be able to get some marketing data from an industry trade association or from other businesses within your specific industry.
Corrective Plan. A marketing plan is a living document. Trust me, the moment you have it and experience planning your marketing, you will realize this. Therefore it is a plan that allows you to assess past strategies and results and at the same time allow you to make necessary corrective measures to fit your business growth. for example, who expected the 2008 financial crisis to hit us so badly? No one other than the few so called "economists" but how did responded to it? Severely. Many businesses closed including many giants. But the good thing is, many have a solid marketing and business plans, therefore they make quick corrective actions and moved forward.