The really important person to your business is the person or persons who are buying whatever it is (what) you are selling. If this is true, then it also follows that maybe the person or persons who may buy what you are selling also deserves some attention.
This suggests that you should know the names of these people so that you can tell or in some way let them know all about what you have to offer. In addition to identifying the people by name, knowing the name of the company or organization they represent adds important information. Some businesspersons are of the opinion that knowing the name of a company or organization gives a clue to the expected sale. In other words, how much can we get from that person in sales!
In a secondary sense, knowing the location of the person or business helps plan for efficient management of your marketing time and plan. Knowing possible locations or addresses of where people, who buy what you are selling, exists suggests places for you to look.
Example. Let's imagine that you were responsible for running a department consisting of 10 people, each of who had a desk with a telephone. The desks arranged in two rows were located in one single room. To make things simple, you assigned each desk an unique number using 1 through 10. The first desk was numbered 1, the second desk was numbered 2, and so on. Initially, you had 10 people and each was assigned to work at one of the desks so that each desk had one person working at it. Later, two of the people were moved out of your department which left two of the desks (desk No. 3 and 8) vacant. This meant that if a new person were to be transferred into you department you could put him or her at either desk No. 3 or 8. Even if the two desks were removed from you department when the two people left, you would have an area or location where you could move two new desks in when one or two new people were transferred back into to your department.
The desks had an unique location or address. People or business are like that. They usually have an unique location or address where they can be contacted. If one specific person or business is not at the address, maybe another potential prospect has taken over that address The point is that if you don't know the address or location of where potential suspects or prospects can operate you may not be able to find them until it's to late.