Final answer:
The missing characteristic in the list of ideally insurable risk characteristics is that loss should be a fortuitous loss
Step-by-step explanation:
The missing characteristic in the list of ideally insurable risk characteristics is that loss should be a fortuitous loss. A fortuitous loss is one that occurs by chance or accident, rather than being intentionally caused. This requirement ensures that the loss is unexpected and not within the control of the insured.