Your quote was "the probability could be absolutely zero".

Disagree, unless you are saying that if we remove all know causes, there will never be an incident in which a liferaft is required. You are confusing Probability based on events which have happened and Probability based on the likelihood of them happening in the future.

I would challenge your statement, "The number of incidents is not related to the number of voyages or number of miles." and "They are not randomly distributed across the population, but only occur in a narrow range of specific circumstances."

You appear to be saying that increase in usage will not lead to circumstances that need LRs You can analyse the incidents to understand the circumstances but you cannot prevent similar circumstances from reoccuring.