For some, the best coverage is the cheapest car insurance policy that makes them able to legally drive on the road. For others, the best coverage is the type that covers the full cost of repairs on your vehicle when you file a claim. The only way to be certain you are fully protected is to purchase both comprehensive coverage and collision coverage. Each coverage has its own job to do.
The key difference in collision vs. comprehensive coverage is that, to a certain extent, the element of the car driver's control. As we have stated before, collision insurance will typically 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," that are typically out of your control when driving. These can include such events as a spooked deer, a heavy hailstorm, or a carjacking.
An insurance underwriter's job is to evaluate a given risk as to the likelihood that a loss will occur. Any factor that causes a greater likelihood of loss should theoretically be charged a higher rate. This basic principle of insurance must be followed if insurance companies are to remain solvent.[citation needed] Thus, "discrimination" against (i.e., negative differential treatment of) potential insureds in the risk evaluation and premium-setting process is a necessary by-product of the fundamentals of insurance underwriting. For instance, insurers charge older people significantly higher premiums than they charge younger people for term life insurance. Older people are thus treated differently from younger people (i.e., a distinction is made, discrimination occurs). The rationale for the differential treatment goes to the heart of the risk a life insurer takes: Old people are likely to die sooner than young people, so the risk of loss (the insured's death) is greater in any given period of time and therefore the risk premium must be higher to cover the greater risk. However, treating insureds differently when there is no actuarially sound reason for doing so is unlawful discrimination.
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.[25] 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.

Let's use the aftermath of Superstorm Sandy as an example to illustrate the differences between collision and comprehensive. Within that storm, let's consider two events that might have happened: 1) a heavy tree branch fell on your car, or 2) you swerved to avoid a falling tree branch and wound up crashing into a tree. In the first event, you had no control over when or why a tree branch would fall on your car. This kind of accident would get reimbursed under your comprehensive policy. In the second situation, you were driving the car and ultimately swerved into the tree, which makes it a collision, and collision insurance therefore pays for the damages. Events like the hypothetical ones stated above are why it's important to differentiate between the two types of coverage.

Protected self-insurance is an alternative risk financing mechanism in which an organization retains the mathematically calculated cost of risk within the organization and transfers the catastrophic risk with specific and aggregate limits to an insurer so the maximum total cost of the program is known. A properly designed and underwritten Protected Self-Insurance Program reduces and stabilizes the cost of insurance and provides valuable risk management information.
Auto insurance will generally cover a driver from any state as long as he has the insured’s permission to operate the vehicle. However, this isn’t always the case. In all instances, when someone else operates the insured’s vehicle, the auto coverage and policy terms may vary greatly depending on the carrier and insurance options selected by the insured. That said, if an insured is driving a company/commercial vehicle which has Med Pay/PIP coverage, that coverage is usually primary over the driver’s personal auto policy, which will be secondary in terms of coverage. There are some exceptions.
As we have seen, this is usually not the right question to ask. However, that won’t prevent inquiring minds from asking – over and over. An answer to the question that isn’t going to be universally correct, therefore, is that insurance that follows the car usually has the vehicle listed in the policy. If anyone who has your permission drives the car, that person is probably covered by virtue of the fact that the car is covered. However, as we’ve seen, this kind of insurance does not cover everyone. There are qualifications for the drivers covered. Other types of coverage such as collision or comprehensive insurance will usually follow the car. These coverages will usually not “follow the driver” to any vehicle which the “covered” driver operates.
If your car is worth more than $3,000 and/or is less than 10 years old, we'd also suggest both collision and comprehensive coverage, too. Our estimates suggest drivers can buy comprehensive and collision insurance for an average of $600 to $700 per year (however, the cost may be higher for some cars), so you would spend $3,000 to $3,500 in premiums over five years. If your car is currently worth less than $3,000, you will have spent more on insurance than your car is worth. You can obtain the estimated value of your car from sites like Kelley Blue Book and Edmunds. Once you have both the value and a quote for coverage, you can determine whether collision insurance will be worth it.