Breadth of disclosure is narrow because many topics are ‘off limits’ at the start of a relationship. If we reveal too much it may even cause the relationship to end before it even got started.
However, as the relantionship grows and develops, self disclosure becomes deeper, progressively removing more layers and revealing out true selves. This means that those topics which were ‘off limits’ at the start may not be now.
Eventually we are prepared to reveal intimate, high-risk information such as painful experiences.