"The promise of reward has even been used to help people overcome addiction. One of the most effective intervention strategies in alcohol and drug recovery is something called the fish bowl. Patients who pass their drug tests win the opportunity to draw a slip of paper out of a bowl. About half of these slips have a prize listed on them, ranging in value from $1 to $20. Only one slip has a big prize, worth $100. Half of the slips have no prize value at all—instead, they say, “Keep up the good work.” This means that when you reach your hand into the fish bowl, the odds are you’re going to end up with a prize worth $1 or a few kind words.
This shouldn’t be motivating—but it is. In one study, 83 percent of patients who had access to fish bowl rewards stayed in treatment for the whole twelve weeks, compared with only 20 percent of patients receiving standard treatment without the promise of reward. Eighty percent of the fish bowl patients passed all their drug tests, compared with only 40 percent of the standard treatment group. When the intervention was over, the fish bowl group was also far less likely to relapse than patients who received standard treatment—even without the continued promise of reward.
Amazingly, the fish bowl technique works even better than paying patients for passing their drug tests—despite the fact that patients end up with far less “reward” from the fish bowl than they would from guaranteed payments.
This highlights the power of an unpredictable reward. Our reward system gets much more excited about a possible big win than a guaranteed smaller reward, and it will motivate us to do whatever provides the chance to win.
This is why people would rather play the lottery than earn a guaranteed 2 percent interest in a savings account, and why even the lowest employee in a company should be made to believe he could someday be the CEO."
The Willpower Instinct: How Self-Control Works, Why It Matters, and What You Can DoTo Get More of It by Ph.D., Kelly McGonigal