300 customers at a car wash were split into two groups and given one of two different loyalty cards for a free wash upon completion: either one with space for 8 stamps or one for 10 (with 2 spaces pre-stamped).

Despite both cards requiring the same amount of effort, completion of the non-pre-stamped 8 card over a 9-month period was only 19% whereas the pre-stamped 10-card was 34%.

Get them started. Endow progress with a fraction of points, stars or a brand-specific measure. Make sure you endow enough to motivate use, aiming for between 10-25% of the total effort required for the first reward.  As well as helping with initial effort, make the reward itself substantial and meaningful to assist habit-forming.

Never endow at the end. The closer we are to a goal, the more we value our own internal efforts to complete it. Doing so on their behalf will devalue existing effort, perceived reward value and reduce loyalty strength.

Make it seamless. In Christmas 2013, 1 in 8 Americans got a Starbucks Gift Card. On redemption they were automatically endowed with progress in the form of loyalty stars, creating 1.5m new loyalty members as a result. How can you seamlessly channel gift customers through to your loyalty scheme?