The teacher can never make the student learn. For example, you should no better than to mix terms of art, but continually do anyway.
Pre-existing conditions are not insurable. Never were. The distinction you continually skip over is that the condition is a risk factor for other issues. For example, coverage is denied for heart issues because of pre-existing diabetes. This is a completely different conversation from a person with a heart condition applying for coverage of his heart condition.
It is painfully obvious you gloss over details. Try, this once, to get it right.
Rule #1: You can insure risk.
Rule #2: You cannot insure expenses.
In the first case, coverage might be granted with a higher premium, a coverage exclusion or a policy rider. Compare, in life insurance to smoker rates or in casualty insurance to DUI rates. In neither case is there to coverage of the diabetes. In the second case, the risk has become certainty. No insurance is possible (the house is burning situation).
When you figure out the distinction between risk and expense, rephrase so I can tell if you figured it out.
J