Peak-End Rule

Experiences are mostly judged by their end or peaks.

This is a draft chapter of Sales Gems: Using Behavioural Economics and Consumer Psychology to Smash Your Target. Preorder it here.

We judge an experience by its most intense point and its end, as opposed to the total sum or average of every moment of the experience.


  • Erase the negative experiences your prospects encounter during a deal.
  • If things go wrong allow flexibility and humility beacuse it will likely save any existing relationship.
  • Influence what is remembered during your presentations by creating strong peaks and ends to them.
  • Don’t try to fix every mistake. More-often-than-not your efforts will not be rewarded.
  • Communicating messaging carefully. Positioning strongly influences the way customers experience your product or service.

One summer, many years ago, I remember vividly watching the Royal Philharmonic Orchestra performing at the Royal Albert Hall. The performance looked to be sold out, there was no sign of an empty seat in the Hall.

I’m not an expert, but what I saw and heard was astounding, as the open-mouthed concert goers around me would attest. The conductor was waving his arms around manically, bringing the woodwinds, brass, percussion, and string sections together beautifully.

At one point the booming acoustics amplified by the venue died down to a single clarinet. It was an elegant solo, until another distinct sound rung out — a mobile phone ringing. The music had been ruined. Peoples expressions of awe turned to frowns for the remaining 5 minutes of the performance. 30 minutes of listening was destroyed by what happened in a few moments at the conclusion.

It would appear we do not perceive the overall experience when judging past events but rather how it was at its peak (e.g., pleasant or unpleasant) and how it ended. The feeling of the peak and end dictates how we remember it.

Since most consumer interactions have set beginnings and ends, they fit the Peak–End Rule perfectly. There is a real opportunity to dramatically change your customers perception and influence their behaviours, without changing your fundamental product or service.

Customer Service

AT&T, a popular mobile phone provider in the US, noticed that it could take several minutes after a customer entered one of their stores for an associate to be available to help. This caused significant anxiety for customers, who would sometimes wonder if they were next, and how long the wait might be. This led to them reporting dissatisfaction, regardless of how the rest of the in-store experience played out.

After many unsuccessful attempts trying to solve this problem, AT&T’s research found that by quickly greeting a customer their perception measurably improved about their overall experience. They did this by greeting each customer entering a store within 10 seconds or 10 feet from the door. The AT&T associates would also shake hands at the end of the interaction, creating a very deliberate, positive moment at the end of the experience.

Not only did the customers greeted in this way report increased satisfaction of the experience, when asked in a survey afterwards, the customers who were greeted quickly also estimated that the waiting time was shorter than it actually was. It seems that changing a simple policy turned what could be a negative “peak” into a positive one.

Research would suggest we judge an experience by its peak and its end, and these experiences can alter our perception of time.

Cold Water

In one of the most widely known experiments examining the Peak-End Rule, 32 participants were subjected to two different versions of a single unpleasant experience (Fredrickson & Kahneman, 1993).

The first trial had participants submerge a hand in 14°C water for 60 seconds (short trial). The second trial had participants submerge the other hand in 14°C water for 60 seconds, but then keep their hand submerged for an additional 30 seconds, during which the temperature was raised to 15°C (long trial).

During the trial participants were asked to record how they were feeling using a dial between 0 (no pain) to 10 (extreme pain). They were also asked to rate overall discomfort following the experiment. Finally, participants were then asked which trial they would choose repeat.

As expected, real-time measures of discomfort were essentially identical for the short trial (8.44) and for the first 60 seconds of the long trial (8.34). The gradual increase in water temperature during the final 30 seconds of the long trial caused a significant drop in the discomfort reported by participants (6.80).

When asked which trial they would repeat, 22 of the 32 (68.8%) participants were more willing to repeat the longer trial, despite a prolonged exposure to uncomfortable temperatures. The participants chose more pain over less pain. Participants also said that the longer trial was less painful overall, less cold, and easier to cope with. Some even reported that it took less time.

It was concluded that participants chose the long trial simply because they remembered the lower discomfort at the end of the experiment, when the temperature increased, and liked this memory better than the alternative (or disliked it less). The results also suggest our perception of time is affected when recalling experience of aversive experience.

Colonoscopy (part 1)

The researchers saw a similar result when studying patients who had undergone a colonoscopy examination.

154 participants who were scheduled for a colonoscopy agreed to take part in the study (Redelmeier & Kahneman, 1996). Given the colonoscopies were being carried out for genuine medical investigation, the actual time varied considerably; between 4–67 minutes for each colonoscopy, though the patient had no knowledge of procedure length in advance.

During the procedure participants were asked to record how they were feeling using a dial between 0 (no pain) to 10 (extreme pain) every 60 seconds. They were also asked to rate their overall discomfort following the procedure.

Pearson correlation coefficient (r) is a measure of the strength of the association between the two variables. Data ranges from -1 (no correlation) to +1 (high correlation).

Patients retrospective discomfort ratings of the procedure correlated most highly with the peak pain they reported during the colonoscopies (r = 0.62). Similarly end pain also correlated highly with the patients retrospective view of the pain experienced during the procedure (r = 0.50). There was no significant correlation between the duration of the procedure and the patient’s average reported intensity of pain.

Patients memories of painful medical procedures largely reflect the intensity of pain at the worst part and at the final part of the experience as opposed to the average overall duration of pain.

Colonoscopy (part 2)

The researchers then expanded the experiment 6 years later to examine how the Peak-End Rule might affect future behaviours and choices.

This time 682 participants scheduled for an upcoming colonoscopy agreed to take part in the study (Redelmeier & Kahneman, 2003). Again, no colonoscopy was performed solely for research.

In this study, participants were split into two groups. Participants in the first group had the colonoscopy conducted as normal (conventional procedure). For the second group, the researchers wanted to minimise the level of pain during the final minutes of the procedure and thereby allow the patient to retain a more positive memory of the experience (modified procedure). To do so, the tip of the colonoscope was allowed to rest in the rectum for up to 3 minutes prior to removal.

During the procedure participants were asked to record how they were feeling using a dial between 0 (no pain) to 10 (extreme pain) every 60 seconds. They were also asked to rate overall discomfort following the procedure.

Upon examining the data, researchers found no significant difference between the two groups in the level of pain during the initial part, the middle part, and the worst part of the colonoscopy procedures. As expected, the level of pain during the final part of the procedure was lower for patients who received the modified procedure versus the conventional procedure (1.7 vs. 2.5).

Curiously, patients who received the modified procedure remembered less total pain (4.1) compared to the conventional procedure (4.6).

Even more curiously, 42% the participants who had never received a colonoscopy before and had the modified procedure returned for a repeat procedure. Only 32% of the participants that had never received a colonoscopy before and had the conventional procedure returned for a repeat procedure. Researchers again concluded this was because a less painful end in the modified procedure led patients to evaluate the procedure more positively than those who faced the conventional procedure.

Not only do experiences of painful medical procedures largely reflect the intensity of pain at the final part of the experience, patients’ memories of the past may influence their decisions about the future.


Another group of researchers wanted to test if the the Peak–End Rule also applied to material goods, rather than just pain.

104 participants who had donated money to non-profit organisations were emailed and informed they had won one or two DVDs from a raffle they had previously entered (Do, Rupert & Wolford, 2008).

In the emails participants were presented with the opportunity to select free DVDs from one or two predetermined lists, depending on which group they were placed. List A consisted of 10 movies that were rated highly on Rotten Tomatoes (very pleasing experience); List B consisted of 10 movies that were rated positively on Rotten Tomatoes (mildily pleasing experience), but less so than those on List A.

The participants were randomly divided into one of five groups. Group A received a DVD from List A only. Group B received a DVD from List B. Group A+B received a DVD from List A and a second DVD from List B, and so on. The participants in groups that were told they had won two DVD’s only viewed the second list in a second e-mail after they had chosen their first DVD.

After making all of their DVD selections, participants were then asked to rate how pleased they were with the overall experience of receiving the DVD prize on a scale that ranged from 1 (least pleased) to 7 (most pleased).

As hypothesised, researchers found that those offered the very pleasing experience, selecting DVDs from list A only, reported significantly higher levels of satisfaction of the experience (5.21), than the participants selecting DVDs from list B only (2.57).

The results of this study support the idea that the effects found in retrospective evaluations of pain are also applicable to evaluations of pleasure.

Sales Gems

  • Service recovery is key
    Negative occurrences in any customer interaction can be counteracted by establishing a firmly positive peak and end. If a mistake is made and immediately corrected, customers tend to forgive easily. This can be achieved in many ways, such as giving out free samples, pro-active after-sales care via social media or paying a staff member to smile as they hold the shop door for customers as they leave.
  • Identify some peak positive experiences
    You tend to know some particular experiences that customers have appreciated in the past. For example, a great restaurant owner might serve a complimentary small dessert at the end of a meal making it seem less expensive! Even during online based sales, sincere thank you’s after purchase can make a real difference to the overall customer experience, and subsequently their likelihood to return and refer.
  • Look out for peak negative experiences too
    Experience highlights some frequent customer complaints too. Addressing these on priority is a good idea. If you cannot eliminate some known negative experiences systematically, try to right perceived wrongs immediately. This will help with your customer experience.
  • It’s your job to fix mistakes
    A really good salesperson who helps with an exchange can erase negative experiences along the way. The long wait in line and the bad music in the changing room are forgotten.
  • Design empathic product experiences
    If things go wrong, which they naturally do, whether through fault of the consumer or a failure of the product experience itself, allow flexibility, humility, and an opportunity to save the relationship.
  • Don’t sweat minor mistakes
    When a small mistake is made, you might be tempted to spend hours fixing it. Whilst this might seem like good practice, think about the opportunity cost of doing so. A simple mistake might be forgotten by a prospect in favour of the most favourable experiences (or worst) during the deal.
  • Apply during meetings and presentations
    Have you ever heard the phrase “go out on a high”? The Peak-End rule proves there is science behind it. For speakers looking to get a point across, make sure it is made at the peak and end of talk.
  • Create positive memories for your team
    Managers should create positive moments for their staff as well as treat them pleasantly when they leave. This will positively affect their memories of the workday and their job which in-turn will likely lead to them staying loyal and motivated.
  • Think about communicating messages carefully
    As shown in the DVD experiment, products positioned in the right way can make them remembered more favourable. Instead of just winning DVDs, the participants won highly rated DVDs.

As a small thank you I’d like to offer you 50% off my upcoming book Sales Gems. Claim your discount here.

This is a draft chapter of Sales Gems: Using Behavioural Economics and Consumer Psychology to Smash Your Target. Preorder it here.