About 5 years ago I was contacted by a young man who wanted to be baptized. I made arrangements to meet him at a beach in NJ. I spoke with him about baptism and other important matters and then we both went into the cold ocean water. Afterwards, he was very grateful and excited. His parents were even there to witness the event. Less than a year later, he told me that he didn't believe anymore. I must confess that I didn't stay in touch with him for discipleship, but I don't overemphasize my responsibility for his falling away. The scripture shows us that even though we are called to make disciples, the main responsibility lies with the person confessing faith in Christ. In Acts 8 Philip is told by the Spirit to engage an Ethiopian Eunuch who is reading scripture while sitting in his chariot. Philip explains the gospel to him and the Ethiopian Eunuch asks to be baptized when they come upon water. Philip says he will baptize him, but his posture isn't that of just handing out baptisms like handing out candy to children. He says he'll baptize him only if he truly believes. Philip had a posture that put across the point that a person needs to be very clear about their decision to follow Christ. Also, there's no indication of Philip ever discipling this man. If anything, the scripture is clear that the Ethiopian Eunuch never saw Philip again.
Acts 8:35-39 makes this clear.
Then Philip opened his mouth, and began at the same scripture, and preached unto him Jesus. And as they went on their way, they came unto a certain water: and the eunuch said, See, here is water; what doth hinder me to be baptized? And Philip said, If thou believest with all thine heart, thou mayest. And he answered and said, I believe that Jesus Christ is the Son of God. And he commanded the chariot to stand still: and they went down both into the water, both Philip and the eunuch; and he baptized him. And when they were come up out of the water, the Spirit of the Lord caught away Philip, that the eunuch saw him no more: and he went on his way rejoicing. - Acts 8:35-39