“And the things you have heard from me, in the presence of many witnesses, these entrust to faithful men, who will be able to teach others also.” 2 Timothy 2:2
When God calls a Disciple to disciple another person, he doesn’t just say to disciple anyone, but rather we are to disciple those who will be faithful with what is being entrusted to them. A disciple understands that to invest their lives in someone who will not be “faithful” is to squander the valuable possession that has been entrusted to them. Even Jesus said that we must be careful not to “cast your pearls before swine.” (Matt. 7:6)
Think of it this way. If the person who discipled Billy Graham had instead spent all of their time trying to get an uninterested man to commit to the life of a disciple, and Billy Graham failed to grow and mature as a result, what would have been the impact on the Kingdom? If you and I spend all of our time chasing those who are “not faithful”, the ones who are faithful and earnest in their faith will suffer. It’s not that every person isn’t important, but not every person chooses the path of faithfulness.
HarvestInsider 
Yet I have noted that planting a seed with a scoffing friend, what ever brief that moment was, has years later come to fruition.