Imagine this: Not long after getting word that you are HIV positive, you receive a letter from your insurance carrier. They're revoking your coverage because, upon examining your medical records, they've decided you knew about your condition and hid it from them. You have no idea what they are talking about; you bought this policy before the diagnosis. But when you inform them of this, and even provide some evidence that their investigation is in error, they ignore you. Meanwhile, you're on the hook for unimaginable medical bills, since you're uninsured and there's not a carrier in the world that will take you now.
This bill is not perfect in anyway. But the status quo is criminal.