Tell them that every business for that matter started from scratch and it will take time for them to grow. In SFI all affiliates that signed up were ask to make their GOALS, why because this will be the determining factor how you will persist in doing your business as it is in SFI. With the set goals in hand, this will become their motivational factor to help reach their GOALS. So give time and effort to your SFI business. Hope this help.
