Before you embark on any meaningful marketing journey, you must know who you are as a brand/organization/company because that will inform your messaging and how you express yourself across all mediums.
Who you are is a composition of your experience (either individual or shared, depending on whether you are a sole proprietor or a group of individuals), knowledge, skillset(s), and approach to customer service, among many other things. Being able to communicate the sum of these parts is critically important in reaching your target market, being relevant to them and triggering an emotional response to buy your products or services.
This information also serves as a guiding light for your organization, through thick and thin, because your values, mission and vision stem from these attributes. The time is over where you could offer a product or service with no personal interaction at some level with the customer. Your market craves knowing who they are buying from, what you stand for, and how you are going to help them. Knowing who you are answers those questions. Period.