What appears accidental can still be predictable.

Accidents can be entirely predictable in aggregate. Nobody plans the specific incident, but if the conditions make it likely, then something of that kind was always going to happen eventually to someone. The particular timing is chance; the category is design.

Instead of asking whether a specific bad thing will happen, ask whether your setup makes that class of thing likely. If it does, the fix is structural, and it is available before any incident, which is the only time it is cheap.