Even successful telemarketers have an estimated 96 per cent chance of being turned down, says one company

With odds so low, out of sheer desperation, we will be relentless in trying to keep you on the phone. You can’t just screen my calls using caller ID. If you don’t pick up, I mark your lead (our lingo for file) as ‘no answer’, and the system programs another call for a few days later. If my company does not have a large lead pool, you may get called as soon as 12 hours later. If you’re dealing with this kind of aggressive campaign, it’s actually better to answer than to let the phone keep ringing.
When you answer, I’ll try to sell the product to you using the ‘Three No’s rule: Don’t let the customer go until she has said no three times during the phone call. After the first two times the client say ‘no’, they become more likely to spend money. If you don’t purchase the item, I will log everything you’ve said and suggest calling you back another time. These are logged as ‘callbacks’ – tiny gold nuggets for telemarketers to follow up on. And thus, the cycle continues. Now that you know how I work, here’s how to make me go away for good.
Don’t immediately hang up

If you do, I’ll mark your lead as ‘no answer’ – the same status as if you had never picked up in the first place. Then I will call you back until I have a conversation with you. And if you hang up mid-conversation without an explanation, I will most likely call you back and claim that you got disconnected.
If, however, you receive a call and immediately hear the phrase “Can you hear me?” – hang up. The phrase is used to coax you into saying “yes”, a word that, if said in your voice, is as good as gold for con artists.
Don’t engage me in any way

Interaction gives me the false hope that you may just need some convincing to buy my product. Do not ask any questions. Do not try to explain why you are not interested in the product. Do not show empathy, compassion or any other human characteristic.