How the Peak-end Rule affects user experience
What is the Peak-end Rule?
The peak-end rule affects how we remember an event by simplifying the memory and emphasising its peaks and endings. We tend to remember a memory or judge an experience based on how they felt at peak moments and at the end.
The Study
In a study titled “When more pain is preferred to less: Adding a better end” by Kahneman, Fredrickson, Schreiber and Redelmeier, participants were exposed to two different aversive experiences. In the short trial, they were asked to immerse one hand in water at 14°C for 60 seconds. In the long trial, they immersed the other hand in the water 30 seconds longer as the water was gradually raised to 15°C. When asked which experience they were to repeat, a significant majority chose the long trial. The authors concluded that duration only plays a small role when we recall aversive experiences. The authors concluded that participants chose the long trial because they liked the memory of it better than the alternative (or disliked it less).
“Evaluations are often dominated by the discomfort at the worst and at the final moments of episodes”
In another study conducted by Kahneman and Redelmeier in 1996 which assessed patients’ appraisals of two minimally invasive treatments, they found that patients consistently evaluated the discomfort of their experience based on the intensity of pain at the worst (peak) and final (end) moments.
Causes
The Peak-end rule can be explained by the memory bias and recency bias.
Our memory tends to be biased towards events that are more emotionally intense, therefore the peak moments would leave a deeper impression on us.
Due to serial position effects, we remember better both the beginning and end of a memory. Recency bias gives greater importance to the most recent event.
How can we use the Peak-end rule to improve user experience?
When designing interfaces and experiences, pay attention to the most intense points of a typical user journey (the peaks) and the final moments (the end). How can we use the Peak-end rule to improve user experience?
1. Identify the peaks in a customer journey
Journey mapping is a useful process that provides a holistic view of the customer experience by uncovering moments of both frustration and delight (the peaks) throughout a series of interactions.
With the customer’s process visualised in a journey map, it reveals the most delightful moments and also opportunities to address customers’ pain points.
2. Create memorable and positive peaks
Low points — The low points are where users experience the most frustration or friction. They are usually represented visually as dips in the journey map. Identify these pain points and think of how you can implement solutions that improve their experience.
High points — Look at the high points in the journey, which interactions are users happy with? Think about how you can amplify these positive moments and recreate similar experiences elsewhere in the journey. Positive peak experiences can be easily created by simple actions such as simplifying a process or remembering user details.
Include elements that highlight moments of convenience, comfort and even delight to transform a pleasant experience into a memorable one (e.g. bright colour, icon, lively illustration at the end of a successful interaction).
3. All’s well that ends well: End on a good note
According to the Peak-end rule, we give greater importance to the last moments when we are judging an event. This is an opportunity for negative occurences to be counteracted by delivering a positive end experience. It can be anything from memorable and enjoyable music, free sample, follow-up call or providing a feeling of success, flow and accomplishment.
The next time you are designing a user experience, keep in mind how the peak-end rule affects how users evaluate an experience of using your product.
