Other than that, we really don't need to know.
But what you're not understanding is that, as divers, we do need to know. We need to know if it was something preventable so we can avoid putting ourselves into a similar situation. Training for cave diving was founded on accident analysis. It's hammered into us that accident analysis helps us prevent future accidents. So, for some cave divers it becomes a natural tendency to want to analyze any accidents that occur.