Definite loss: The loss takes place at a known time, in a known place, and from a known cause. The classic example is death of an insured person on a life insurance policy. Fire, automobile accidents, and worker injuries may all easily meet this criterion. Other types of losses may only be definite in theory. Occupational disease, for instance, may involve prolonged exposure to injurious conditions where no specific time, place, or cause is identifiable. Ideally, the time, place, and cause of a loss should be clear enough that a reasonable person, with sufficient information, could objectively verify all three elements.
Retrospectively rated insurance is a method of establishing a premium on large commercial accounts. The final premium is based on the insured's actual loss experience during the policy term, sometimes subject to a minimum and maximum premium, with the final premium determined by a formula. Under this plan, the current year's premium is based partially (or wholly) on the current year's losses, although the premium adjustments may take months or years beyond the current year's expiration date. The rating formula is guaranteed in the insurance contract. Formula: retrospective premium = converted loss + basic premium × tax multiplier. Numerous variations of this formula have been developed and are in use.

Insurance terms, definitions and explanations are intended for informational purposes only and do not in any way replace or modify the definitions and information contained in individual insurance contracts, policies or declaration pages, which are controlling. Such terms and availability may vary by state and exclusions may apply. Discounts may not be applied to all policy coverages.
Insurance can influence the probability of losses through moral hazard, insurance fraud, and preventive steps by the insurance company. Insurance scholars have typically used moral hazard to refer to the increased loss due to unintentional carelessness and insurance fraud to refer to increased risk due to intentional carelessness or indifference.[22] Insurers attempt to address carelessness through inspections, policy provisions requiring certain types of maintenance, and possible discounts for loss mitigation efforts. While in theory insurers could encourage investment in loss reduction, some commentators have argued that in practice insurers had historically not aggressively pursued loss control measures—particularly to prevent disaster losses such as hurricanes—because of concerns over rate reductions and legal battles. However, since about 1996 insurers have begun to take a more active role in loss mitigation, such as through building codes.[23]
The main difference between collision and comprehensive coverage comes down to the question of what the driver controls. Collision insurance will cover events within a motorist's control or when another vehicle collides with your car. Comprehensive coverage generally falls under "acts of God or nature," or things that are typically out of your control when driving. These can include events such as a spooked deer, a heavy hailstorm, or a carjacking.