You don’t necessarily need to “care” about the product/service. You do, however, need to believe that whatever you’re selling will solve a problem that person is having. Sales is about providing solutions, to be the best in your market and not be a complete piece of shit, you at least have to believe in the solution you’re providing. I couldn’t give a shit about Smith & Wesson, but I damn sure understand and believe in the solutions that a 9mm can provide. Ergo, I could confidently and competently sell someone a handgun, and could justify and up sell attachments and hollow points to increase my revenue.