To be good at sales you must let people sit in their own pain. The reason people are interesting in your product is because they have a current agitated state and your product can move them into their desired state. You are the link between their current state and their desired state. If they do not buy your product they will stay miserable. This is not rude but you must point this out to them.
Ask probing questions to evoke an emotional response like what is their current pain and frustrations? What are their goals? What are they willing to do to get their?
Have confidence and influence people for their own good.