Confession alone has psychological advantages. However, if someone has deep-seated aversion to uprooting a particular sin, it may take seemingly countless promptings from the Holy Spirit. I do not know how to answer your question though.
The Greek word for repentance metanoia connotes experiencing a change in one’s being. So, incrementally or not, we are transformed from the Sacrament and we should intend to make each act of contrition our last.
