When we ask Mark Joyner why businesses have only three seconds to make a sale, the author of The Irresistible Offer: How to Sell Your Product or Service in 3 Seconds or Less points to two reasons: the exponentially expanding volume of information and the limited time consumers have to evaluate marketing messages.

He launches quickly into why you need to keep it short.

Entrepreneur: How do you make an offer irresistible?

Mark Joyner: The irresistible offer has three elements: high ROI, a touchstone and believability.

Each of these is extremely important, but at the core, what you offer must have a high return on the consumers' investment.

Touchstone is that three-second-or-less tag line that sums up your offer and answers as many of the big four questions as possible: What are you selling me, What is the cost, Why should I believe you, and What's in it for me?

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