What is insurance?

Insurance is a deal. You pay a small, known amount on a schedule, and in exchange a company promises to cover a large, unknown loss if it ever happens. You are swapping a small certain cost for protection against a big uncertain one. That single swap is the whole industry.

The pool

Here is how the machine works underneath. Thousands of people who face the same risk each pay a regular amount, called a premium, into a shared pool run by the insurer. In any given year, most of them will have no disaster at all. A few will. The pool pays for the few, and the insurer keeps some of what is left as profit for running it. Insurance is really just organised sharing of bad luck.

This is why insurance can pay out far more than you ever put in. If your $1,000 of premiums is met with a $40,000 payout after a crash, the extra $39,000 did not come from the insurer's generosity. It came from everyone else in the pool who paid and claimed nothing that year.

Why the pool is predictable

There is a reason this works for the insurer and not only for you. No one can predict whether a particular driver will crash next year, but across a hundred thousand drivers the number who will crash is remarkably steady from one year to the next. A single coin toss is a mystery. Toss a coin ten thousand times, however, and it lands close to half heads every time. Insurers rely on exactly that effect. They cannot say which house will burn down, but they can estimate how many will, and that estimate is steady enough to set a premium that covers the claims with a little left over.

Put some illustrative numbers on it. Imagine a thousand drivers who each pay $1,000 a year into a pool, so the pool holds $1,000,000. Suppose that in a normal year twenty of them have a serious crash costing $40,000 each to put right, which comes to $800,000 in claims paid out of the million that came in. That leaves $200,000 to run the business and to absorb the harder years when more than twenty crash. Every one of those thousand drivers paid the same $1,000. Twenty of them got $40,000 back. The other nine hundred and eighty got the one thing they were actually paying for, which was the certainty that if they had been one of the twenty, they would have been fine.

You are supposed to lose, most years

In most years you will pay premiums and get nothing back, and that can feel like wasted money. It is not. What you bought was certainty: a year in which no single accident could wreck your finances. Judging insurance by whether you claimed is like judging a seatbelt by whether you crashed.

Insurance in Australia

Australians insure cars, homes, belongings, health, travel and income. Most of it is optional, and choosing well is a real skill. One piece is not optional: compulsory third party insurance, called CTP and known as a green slip in NSW, comes with every vehicle registration in every state and covers injuries to people hurt in accidents. Everything beyond that is your call, which is what the rest of this topic is about.