Why would you purchase comprehensive general liability insurance?

If you are in a business that involves the risk of accidents, you can be sued for large amounts of money in the event of an accident, therefore you need comprehensive general liability insurance to protect you if you were to lose a large lawsuit.

That is incorrect. I had comprehensive general liability on my Motorcycle. Wrecked it an was not covered because I did not have colllision coverage.
General Liability covers the injuries, repairs of others involved in a wreck where you are found at fault including property, for the amounts stated in your policy. Also there are statewide minimums for each category. Your vehicle is not covered. If you are hit the other drivers insurance pays for your vehicle, if they are uinsured then your policy pays because you are required to have uninsured protection on your policy. If you wreck your car you do not get it repaired by your insurance company with liability. Comprehensive covers damaged to your vehicle incurred by weather, fire, vandalism, etc.. When you get comprehensive coverage you will select a deductible that you must pay and your insurance will pay the rest. For example: a tree branch falls on your car while it is parked somewhere. Comprehensive coverage is for that.