Both aggressiveness and passion are traits present in good salespeople. Aggressiveness keeps them from giving up even in the face of someone that is seemingly uninterested. Passion is the trait that closes the sale. These traits can quickly move from being very similar to very different.
As with so many other things it’s about the balance that you give the two traits. You can’t only lead with passion because passion can wear on the nerves of someone not open to it yet. Similarly aggressiveness can alienate. You can’t alienate your target before finding a way to convince them of your cause.
And there lies the rub – too often salespeople can be in the wrong mode without even thinking about it. Being passionate at the wrong moment can lose just as being aggressive can.
Judge your audience and think of the approach before just diving in.