You can identify a benefit by following the feature with the words “so that.” Say you want to sell parents on child immunizations. The feature by itself, “serum delivered by means of sticking a needle in your child’s arm,” is hardly compelling. But by adding “so that,” you might end up with, “…so that your child can escape pain and possible death from a horrible disease.” I don’t know about you, but I find that a bit more persuasive.