Somewhere I once read that when you're looking for job you shouldn't ask your close friends, because they know everyone you know. You need to ask your acquaintances because they can lead you to new connections.
Bring that over to making disciples. Sometimes we miss the obvious that we should disciple those closest to us. But if we're getting that, it may be time to disciple acquaintances... which can lead to new connections. (This isn't a call for a business model to discipleship, it's a call to spread the Good News on relational networks: Networks that you're a part of and God wants to use you to change for his glory.)