Now, as far as insurance goes, it's the same as any insurance someone may purchase.. home insurance, car insurance, life insurance, etc.
The idea of insurance is companies exist that are willing to take a risk on the fact they can create a large enough group that what they take in will be less than the amount individual participants in the group will claim; the amount they have to pay out.
It does make sense then that the larger the numbers of people insured with the company, the more the risk is spread out.
In terms of health care apparently until now, those insurance companies preferred to lower their risk (and improve their chances at making more profits) by limiting or denying the insurance of people who they are likely to have to pay out more claims for (pre-existing conditions), and also set limits on the amount they are willing to pay out in a lifetime.
In Canada, and in other countries, the governments have basically chosen to be the insurance company. One of the results of that is we pay higher taxes; so we really our paying for health insurance, but it's "included" in what the government supplies for our taxes, rather than an additional expense. It in essence makes the entire population one group, so spreads the risk of health coverage amongst everyone.
There are some variables in health care from one province to the next, but the essence of the system is the same.
One thing that the gov't health insurance doesn't cover in Canada is prescription drugs (if you are outside of a hospital). If you want insurance to cover that type of additional expense you do have to purchase it separately. Some employers offer that coverage as a benefit, some do not.
I haven't checked health insurance around the world because they aren't the reality I have to deal with. But I assume there are no perfect systems anywhere.
I can tell you that I've had a LOT of experience with our health care system in the last dozen years, as my parents aged, and the majority of the time the care has been very good.
My father passed away at 92 yrs. of age. But at 81 he had stomach cancer, and his surgery was done quickly, and was effective in giving him another 11 yrs of life.
My mother is 85, and suffers from worsening dementia. She was in the hospital in Sept, and her treatment was excellent. After leaving the hospital she was sent for a geriatric assessment, where a team of 6 different specialists examined and ran tests to determine if there was something that could be done to improve her life.
To date we've been able to keep her in her own home, with a live in 24 hr. caregiver, as well as a weekend person to give her time off, because of a program the government provides called "self managed care". This program provides her with $2700 /mnth. to assist us in paying for that 24 hr care.
Some people would wonder why they should help paying for her help. But, the thing is, all her life she paid her taxes along they way, as did everyone, so that same assistance is available to all. It is of course hoped that there are more people who don't end up needing it than do.
BUT... 30 years ago, we were on vacation with my parents in Palm Springs, CA, when my mother suffered an huge heart attack. She was in ICU for several weeks, and we were told she would not likely survive. Thankfully she did.
However, the bill for her treatment there was, even at that time, $154,000. If she had not had travel insurance coverage then, my folks would have been bankrupt and likely lost the home my mother still lives in.
And sickness really should not do that to anyone! That's why I've been in favor of universal health care, even with its shortcoming and flaws. I'm willing to keep paying my share of the taxes to make sure no one else faces the possibilities my parents may have faced.