Upon termination of a given policy, the amount of premium collected minus the amount paid out in claims is the insurer's underwriting profit on that policy. Underwriting performance is measured by something called the "combined ratio", which is the ratio of expenses/losses to premiums. A combined ratio of less than 100% indicates an underwriting profit, while anything over 100 indicates an underwriting loss. A company with a combined ratio over 100% may nevertheless remain profitable due to investment earnings.
Adjusting liability insurance claims is particularly difficult because there is a third party involved, the plaintiff, who is under no contractual obligation to cooperate with the insurer and may in fact regard the insurer as a deep pocket. The adjuster must obtain legal counsel for the insured (either inside "house" counsel or outside "panel" counsel), monitor litigation that may take years to complete, and appear in person or over the telephone with settlement authority at a mandatory settlement conference when requested by the judge.
Know when to cut coverage. Don’t strip away coverage just for the sake of cheaper insurance. You’ll need full coverage car insurance to satisfy the terms of an auto loan, and you’ll want it as long as your car would be a financial burden to replace. But for older cars, you can drop comprehensive and collision coverage, which only pay out up to your car’s current value, minus the deductible.