Discipleship is not something that is a bonous. It is something that is commanded by Jesus Christ through the great commission. ~ Go make disciples of all nations ~ We need to undestand that God did not simply ask us to fill up the seats with people. He wants us to make disciples and discipleship involves not only a change in alleigance from the side of darkness to the side of heaven, it also involves changed habits, changed concepts and basically a changed life.
This does not happen magically in a person but often through a period of struggle and persistance, discipleship can take place.