To explain it very simply, Versa Points are what help us to gain rank in SFI. The higher the Versa Points for the month (along with other qualifying features) the higher a person's rank is for the month.
Each month we all start of as Affiliates and gain rank through the month. Hence, at the beginning of each month the Versa Points are rolled down to 0 so that we all start at the same level and then the superstars start showing up through their Versa Points collections for the month.