Conrad Mbewe makes some good points here on motivational speaking in a Christian context:
I think the analysis could benefit from something extra. I think the responses to the young man needed to go deeper. The man had a wrong view of "success". His view was, as Mbewe points out, self-centred rather than God-centred.
That comes down ultimately to the question "what kind of world are we living in?"
The Christian answer is "one made by, through and for Christ. One which is fallen and which Christ has redeemed. One in which 'success' does not mean getting your glory now, but taking up the cross and following Christ so that we can be part of the new creation when he completes the renewal of all things."
The young man really needed someone to change his narrative of reality. Telling him that he is a sinner under the wrath of a holy God is part of this. But what else? How does this relate to the question of "success"? Is repentance a means to worldly prosperity, or something else? What does discipleship look like? The gospel actually needs to not just change our view of self, but of the whole narrative of reality. The very meaning of the word "success" is what is at stake - not simply the issue of how to get it.
I'm thinking that, in Africa just as in the West where the Biblical narrative has disappeared from society's shared assumptions, we need to begin further back. We need to lay the foundation of a Biblical view of reality - of creation and fall and redemption - before we can proceed to talking about sin, otherwise our hearers fail to understand us. In the anecdote Conrad tells, the young man did not see that he was chained by sin and that that was his major problem. But as I read the anecdote, one of those chains - one of the ways that sin was working in the young man - was in enslaving him to a counter-biblical narrative of what the word "success" meant. The problem was deeper than the surface issue that the man was focussed on "success" instead of upon salvation. His problem was that he had defined success in terms of personal enjoyment of life upon the sinking ship of the "old age" that is doomed to destruction, rather than in terms of participation in the resurrection life of Christ. Christianity does offer "success"; but a different, better and deeper version than the corruptible trinkets of the present age.