For bonus points let's also assume that the user is 2100 away from their lifetime cap in scenario three: then instead of you and your insurer splitting the 1k bill evenly your insurer would split 800 with you (400 from each of you) before saying "peace bro im out" and leaving you with the remaining 200 dollar bill.

Additionally the user above was assuming that insurance would cover half the bill - that's actually a variable that your personal plan might disagree with called your "coinsurance" rate, you could have a 50% coinsurance rate, an 80% rate (an awful plan) or a 0% rate which would mean you're fully covered after you hit your deductible (assuming there aren't any annual coverage cap shenanigans).

Also fun is out of network stuff, different plans may vary but let's take scenario three again but assume the HCP you went to was out of network and their charge master (see parent's footnote) says the actual raw cost of the procedure is 23,000 dollars. Your insurer might handle this in two ways:

1. "get fucked" - your insurer offers no coverage at all for out of network charges - in this case the 23k bill goes against your bank account directly and you likely end up declaring bankruptcy or delinquenting on the loan.

2. "get (slightly less) fucked" - your insurer looks at what you would have paid at an in network HCP and partially pays for your procedure assuming you had it done at an approved HCP. In this case your insurance pays 500 and you just need to cover the remaining 22.5k... so you once again may consider bankruptcy.

In both cases, for shits and giggles, this extreme medical cost does not count toward your OOP - except for 1000$ in the second case if partial coverage is awarded. This is why people Uber to specific hospitals after traumatic injuries.