Our experiencing self and our remembering self are not the same person. Daniel Kahneman shows this in his book Thinking Fast and Slow by gathering survey information from people during unpleasant events and then asking them to recall their subjective experience of the event later. The experiencing self and the remembering self rate the experiences differently.
We can see this in our own lives. During the day you may have had a frustrating project to work on, but when you lay down at night and reflect on the day, you might not remember the project being as bad as it felt in the moment. Alternatively, you might sit around all day binging a TV series and really enjoy a lazy relaxing day. However, you might remember the day much differently when you look back at it, no longer appreciating the experience but regretting it.
With our brain experiencing and remembering events differently, we are set up for some strange cognitive biases when we reflect on past events and think about how we should behave in the future. The Peak-End Rule is one bias that factors into how we remember events and can influence our future choices.
You might expect to rate a poor experience based on how bad the worst moment of the experience was. Say you had to go to a child’s gymnastics routine that you were really dreading. A certain part of the routine may have been all but unbearable to you, but if at the end you found a $20 bill on your way back to the car. Your judgement of the event is going to be influenced by your good luck. Rather than basing your judgement of the show purely on that dreadful routine, or on an average of the whole evening, you are going to find a spot somewhere between the worst moment and the happy moment when you found $20. Its not an average of the whole time, and its not really indicative of your actual experience. A random factor at the end shifted your perspective.
In his book Kahneman writes about the Peak-End Rule as “The global retrospective rating predicted by the average of the level of pain reported at the worst moment of the experience and at its end.” This definition from Kahneman comes after describing a study with participants sticking their hands in icy cold water and subjectively judging the experience later.
The peak-end rule is not limited to painful and unpleasant experiences. Instead of a miserable experience, you could have a truly wonderful experience that ends up being remembered somewhat poorly by a momentary blip at the end. Picture a concert that is great, but flops at the end with the speaker system failing. You won’t reflect back on the entirety of the experience as positively as you should simply because a single song at the end was ruined.
What we should remember from this is that endings matter a lot. Don’t end your meeting with the bad news, end it with the good news so that people walk out on a positive note. The ending of an experience weighs much more heavily than everything in the middle. The points that matter are the peak (either the best or worst part) and the ending. A great ending can buoy a poor experience while a bad ending can tank a great experience. For company meetings, job interviews, or performances, make sure you bring the ending to a high point to lift the overall level of the subjective experience.
Novel Learning 