You need to know everything obtainable about your customers. This list will get you started. You will need their age, sex, marital status, income levels, education levels, geographic locations, where they shop, if they go to church, if they have kids, ages of children, political affiliation, what they like about your company, what they don't like, why they shop with you, what they value about your products/services, what they like the most/least about products/services, and whether prospects are unaware of your brand or products/services. Customers want you to know certain things about them and if you do, they will remain loyal to you as you take time to know them.
I know that most new recruits are told to make that first list quickly and introduce everyone you know to the opportunity. This is the basic old school marketing plan for MLM and it is no longer practical. The problem is this sets the new recruits up to be rejected by people they actually care about, and continuous rejection usually results in the newbie quitting before they ever got very deep into the business.