Talking in terms of their needs is the eager want. By telling them how it benefits them makes them eager to want whatever you're offering. Figure out what would be the most appealing thing for them. For example If you want to convince a friend to go to a particular movie you don't say "I want to go see this movie. Do you want to come with me? "

Instead you say "I know you love this actor and he has a new movie. You should come with me to see it."