Harvard Business Review Suggests Keeping People's Attention By Keeping Them Guessing
Here's one tip from a recent paper.
3. Excite the imagination - Provide some "what if?" scenarios to illustrate the possibilities that await those who manage to come up with creative answers. Paint the pictures but make it clear these are only pictures. Stimulate people to pursue the questions with a lot of energy and creativity.
For instance, simply telling someone they'll receive trade approval for blowing you is a surefire way to make certain that, at best, you get a half hearted BJ with little to no attention paid to the balls. Whereas "What if I told you that administering the best blow job I've ever received gives you some autonomy when it comes to portfolio management?" means you can be sure they're gonna work for it.
Five Ways To Hold The Right Kind Of Attention [Bloomberg]