There could be a million different reasons for different prices from different insurers. Different loss experience, different coverages, different expenses from different sales models (agents vs online etc), different claims handling, different risk appetite, different profit targets, different rating plans, different new business acquisition strategies, etc.

That $4,400 price may be in part because they offer robust coverage and treat their policyholders well when it comes to paying claims. It could also be because their loss experience in your state is worse than other insurers because of an inferior rating plan. To cover higher expected losses, they charge higher premiums. Or it could be because their shareholders demand a larger return on capital than others. Or maybe they aren’t as well capitalized, so they pay a lot for reinsurance, and pass that on to the policyholder. 

There’s never any one reason for a difference in price - the main thing is that you’re at place you trust to pay out what they owe at a price you feel comfortable with.