The point being that in either case - health or auto - the insurance model breaks down if people are allowed to game the system and wait until they have a catastrophe and then sign up for insurance and expect the insurance companies to pay for it. This makes everyone’s rate goes up in order to subsidize someone who refused to buy insurance.
This, I believe, was the point that Rush Limbaugh was trying to make on Thursday that we shouldn't call this insurance. In a sense, our healthcare problem is unsolvable with the idea of insurance as simple risk management. Allowances are going have to be made for those with preexisting conditions, particularly those which are not caused by their behaviors. To some degree, many people are going to pay more than their individual cost to cover the uninsured and the uninsurable.