Underwriting hands you a rate class, and most people read it as a price. It's actually a cost of insurance factor, and where it lands determines how much of every premium dollar gets consumed before anything reaches your cash value.
Inside the policy, premium splits three ways: the cost of insurance for the death benefit, the carrier's expense and policy charges, and whatever's left, which goes to cash value. A better rate class shrinks the first bucket. On a policy built for maximum death benefit, that bucket is large, so the rate class swings the outcome hard. On a policy built for cash value, where the base death benefit is deliberately small and most of the premium is going in through a paid-up additions rider, the cost of insurance is a smaller slice to begin with, so the same rating difference moves the cash value column much less.
That's the part that surprises people who get a Standard offer and assume the plan is dead. On a high cash value design it usually isn't. Run the illustration at the offered class and look at the actual numbers before you decide anything, because the gap between what you feared and what it costs is often a lot narrower than the label suggests.
Table ratings are a different conversation. Those are the substandard classes, usually labeled with numbers or letters, and each step adds a percentage to the mortality charge. A few tables up, the design still works but the funding needs adjusting. Far enough up, a different structure makes more sense.
Two things you can do about a rating you don't like. Ask for reconsideration if the underlying condition improves, since carriers will re-underwrite after a period of stability and most of them don't advertise it. And shop it, because rate classes are not standardized across carriers. What one company calls Standard another calls Preferred, and the same medical history can land two classes apart depending on who's reading it. That's part of why I stay carrier-neutral: the right answer changes by applicant, not by brand.