The goal-gradient effect
The goal-gradient effect says that as a user gets closer to a goal their efforts will increase
Background to this effect
First purposed by Clark Hull in 1932, he found that rats that were placed in a straight alley ran faster as they went from the start line to reaching the food at the other end.
Examples of this effect
Examples of the goal-gradient effect are:
- Profile building progress bars such as LinkedIn or Facebook when they say you have completed 25% of your profile
- Achievements like on the Xbox or Playstation where you see a list of unlocked, in progress or locked achievements
- Credit score or credit card points system which tells you what you need to do to improve your score or if you spend money at a certain store you may get double points
This even applies to charities and donations, a study which looked into this found when the potential donors were told the fund was 10% of meetings it’s goal compared to not being told at all there was no difference in the rates of donations.
Even at 66% towards the goal there was no difference in donations compared to not seeing the progress rate.
Where there was a difference was at 85%, in fact donations doubled when compared to the control variant of not being told the progress rate. The research found that the amount of money being donated by people didn’t increase but the amount of people who donated did increase.
What can you do
One common way of using this effect is to help users along on their journey of completing the goal. An example is when you visit a coffee shop they sometimes give you a stamp card. This stamp card may have something like “get 10 stamps and get your next coffee free!” As well as giving you the card they may also stamp the first one or two which then brings you closer to receiving that free coffee.
This then gives you more motivation and in turn speed to fill in the last 8 stamps as you are already 20% closer to reaching your target.
This idea was actually tested where they tried 2 different coffee stamp cards, the first card had 10 unstamped slots and the other stamp cards had 12 slots but with 2 slots already stamped. This also found that users were more motivated to complete their stamp cards quicker when 2 were already stamped.
This could also be applied online, for example a shopping website could have something like a stamp card which says after purchasing 10 times you then get 20% off your order.
The main point is the user needs to know how close they are to finishing their goal, what they need to do to reach that goal and maybe some encouragement to help them along that journey.