They may not have any converts. But you have a church full of obviously interested people just down the road.
The majority of my friends who left my UMC went to a church that does almost no outreach. They send their kids to our church for VBS and big youth events.
We are a conservative UMC. We only had one liberal Sunday School class and it folded.
I'm coming to the conclusion that churches have no business in outreach - they are the incubator for new and growing Christians to fellowship together and sharpen each other as they worship and hear the Word of God. It falls on these maturing Christians to go out into the lost and dying world with the Good News as they live among and interact with unbelievers. As people respond, they are brought into the fellowship as appropriate.
If any here disagree, please show me from Scripture where the Church as an official organization is tasked with reaching the world.