I guess using the analogy — your doctor won't tell you "you've a great immune system" if you've never caught a bug at all. Maybe you've a really weak immune sys

I guess using the analogy — your doctor won't tell you "you've a great immune system" if you've never caught a bug at all. Maybe you've a really weak immune system, they just don't know. Not going into debt unnecessarily is a great thing, but it's not a data point in your favour, it's the absence of a data point.