1) surgery is dangerous. Even innocuous surgeries can have complications such as infection that can kill. There's also complications that aren't factored into the obvious math, for example ever since I got 2 of my wisdom teeth out, my jaw regularly tightens up and cracks if I open my mouth wide, something that never happened beforehand. I wasn't warned about this and didn't consider it when I was deciding to get the surgery.
2) If it's something dangerous, you're very likely to find out anyway before it becomes serious. eg, if it's a tumor, it's going to keep growing and you can come back a month later and get it out then with little problem.
3) even if it's not nothing, it might be something else that's unlikely to kill you. Thus the 5/1000 chance of death you're imagining is actually a 5/1000 chance of being not nothing.
Are you just making these points as things to keep in mind, or are you making a stronger point? If the latter, can you elaborate? Are you particularly knowledgeable?
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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