My daughter needed a medicine that could only be administered in the hospital. The hospital called our insurance company, and the insurance company said there was no need for pre authorization and that they would cover it. Next thing we know, an $8,000 bill shows up in our mail and a nice letter from the insurance company saying they won't cover the cost. Here in the US, even if you're fortunate enough to have decent insurance, it's no guarantee you won't get stuck with a hefty medical bill.

Incidentally, we're definitely fighting this one and I expect eventually the insurance company will have to pay. However, it has been an absolute nightmare dealing with the insurance company and a huge time sink trying to get this resolved.