The key here is to uncover the prospects wants. This is usually very personal and private. You have to really ask (keep asking why, dig and pry until you get to the core of their emotional buying motive) for they do not want to immediately share this with you until they trust you. But if you ask enough questions the right way, typically they will share it with you. After all, a person loves to talk about the treasure of their hearts.
After you find out what they want, then as you question more about the negative impacts in their life of a lack or shortfall of their current product/ service you will then expose a need that your product/service can help. That is to achieve their goals or to get what they want faster in life (if it was easy they would already have it).
Now, after you have exposed their need you can really start to sell. Who doesn’t want to have what is really important to them?!