I'm often asked what is the most important thing in selling (actually I'm hardly asked at all, but it sounds good!).
Qualifying. In conjunction with kissing a lot of frogs, you can be good at selling (or dating), by knowing the right frogs to kiss.
Those who are great at selling, instinctively know which frogs to kiss, and which frogs to leave well alone.
They've learnt from bitter experience who is going to waste their time or not choose them.
So instead of trying to convince someone who doesn't want convincing, they move on, or they don't spend too much time with them in the first place. You've got to be careful how you reject some frogs, because you might be wrong.
I remember two years ago going into a shop, desperate to buy a new mobile phone and sign for a new 2 years contract. The salesperson at Crazy John's wasn't interested and had decided I wasn't worth the effort. They even moved me on to another supplier (Telstra!), where I got the attention and service. I had to buy that day because my wife needed a new handset before she flew to Sydney the following day. Those 2 years are now up, as of yesterday. Do you think I'm going back to Crazy John's? Nope. Am I going back to Telstra? Nope. Telstra haven't done anything beyond taking the contract.
I digress. In general, you have to think about which frogs you're going to kiss, but not use it as an excuse to not kiss frogs. In fact, for myself, for the first time in 5 years, I've decided to not contact and delete a number of frogs, because in my heart of hearts, they're not interested, and I wonder if I want to do business with their organisations! That's brave of me, but as long as I have some nice frogs, it makes it easier.
You don't have to be a great convincer to be a good salesperson, you can be a good qualifier.