Goal Gradient Effect and How To Motivate Customers To Buy
Goal Gradient Effect and How To Motivate Customers To Buy

Definition
The goal gradient effect means that as people or animals get closer to achieving a reward they accelerate their behaviour to progress towards the goal. People are more motivated by how much is left to reach their target rather than how far they have come. This may be related to the commitment they have invested in the activity which is why commitment and consistency is such a strong motivator.
Evidence of the Goal Gradient Effect:
The American psychologist C Hull developed the goal gradient hypothesis whilst conducting experiments with rats. The rats level of effort rose as they got closer to the food they were being rewarded with.
Psychologists monitored behaviour during a café reward program where customers were given a free coffee after completing ten purchases. They found that customers purchased coffee more frequently the closer they were to receiving a free coffee.
Customers of a music rating website were offered reward certificates to encourage them to rate songs. Those users with reward certificates visited the site more frequently, rated more songs per visit and put more effort into rating songs as they got closer to the reward goal.
Even the illusion of progress towards a reward can be motivational. In the experiment with a café reward program two “bonus” stamps were pre-completed on 12 stamp promotional cards. Other customers received standard 10 stamp cards. However, customers who received the 12 stamp card (with 2 stamps already populated) completed the 10 required purchases faster than those who received the standard 10 stamp card.
The stronger the customer’s inclination to accelerate towards the reward the higher their retention rate and the quicker they re-engaged with the program. This may be related to the psychological desire to be consistent when we show commitment to a behaviour. Commitment and consistency are a powerful motivator of behaviour and this may be coupled with the sunk-cost fallacy if we perceive we have invested significant time or money into something.
Conversion Rate Optimisation
User centred design and Conversion rate optimisation apply the goal gradient effect to ensure users get positive feedback when they interact with a website or app. For example, using a prominent progress bar or indicator to provide users with regular feedback during a sign-up process. Always set the progress bar to show some progress even on the first step as this will help increase your conversion rate. Display a green tick when an input field or drop down is correct. Remember to highlight how close the user is to completing the task.

image Source: Lizearle.com
For example, web forms should always clearly display the total number of steps so that the user understands how close they are to completing it. Forms that don’t show the total number of steps create anxiety. Users may abandon a form because they don’t understand how much commitment there is. The registration form below from Casumo.com has twelve steps, but still has one of the best conversion rates in the sector. Each page is a single question and the total number of steps is clear at the top of each screen.

Casumo.com 12 step registration form
Conclusion:
Ensure that you focus on how close people are to a reward to motivate them effectively. Reward the desired behaviour positively and experiment with different frequency and predictability of rewards.
Ensure progress indicators are prominent and lean towards the end goal in registration and check-out forms. People are motivated by the illusion of progress. Begin by showing progress even at step 1 of your form or checkout.
Free trial periods can benefit from the goal gradient effect by regularly informing users how many days/hours there are before the offer ends. This can help persuade people to upgrade. It highlights how little time there is before they lose access to the service.
Resources:
Rewards and motivations – The psychology of rewards & how to motivate your customers.
Psychological nudges – Inside the Nudge Unit – How small changes make a big impact
Habit formation – The Fogg behaviour model.
Change frameworks – How to use behavioural science to create new habits.
Over 300 tools reviewed – Digital Marketing Toolbox.
A/B testing software – Which A/B testing tools should you choose?
Types of A/B tests – How to optimise your website’s performance using A/B testing.