Herbs and spices should never be used to modify the flavor of a dish.
You should always achieve the exact flavor you are aiming for through the choice and combination of the primary ingredients.
If we are using food analogies we should use one that fits the situation
If your primary ingredients are not good, you can't make a superior dish by adding herbs and spices. You may make it edible, but it would be much better if your primary ingredients were better to begin with.