"Discipleship," as we often do it in our churches, does not work because we are not following the way Jesus discipled others. Jesus was followed by a crowd, but he selected twelve from among them whom he allowed access into his life. Of these twelve, he gave even greater access to three.
He walked with this group, teaching as he went. At the end of the gospel, he charges all followers of his to go to all nations, making disciples as they go (Matthew 28:16-20). This kind of discipleship involved close relationships, time, and simplicity so that the focus could be put on the relationship.
Instead, in churches, we put people into lecture-based classes, teach information, and expect them to understand it and grow from it. Discussion-based classes are a little better, but still fall short of what Jesus did because the relationship, the walking with one another, is missing.
Further, what Jesus did was reproducible. He took twelve men, discipled them, and they became the next generation leaders who shaped, formed, and discipled the early church. They reproduced as well, as believers went from city to city converting and discipling others.
The rise of elders also demonstrates how reproducible early Christianity was, as the apostles appointed elders who would lead, teach and disciple others in the church. Paul taught the same concepts to Timothy, when he told Timothy to entrust what he received from Paul to faithful men who would be able to teach others (2 Timothy 2:2). It was a system of reproducible teaching and a lifestyle of discipleship and mentoring.
The church can only exist as a disciple-making group. The church will only continue into the future if disciples make disciples. We need to find a reproducible way of making disciples and then take initiative to begin discipling. This is the Jesus Way.
For two suggestions on how to disciple others in reproducible ways, consider Life Transformation Groups or Discovery Bible Studies.