Have you ever interviewed a user, after the fact, about an experience and they had nothing but positive things to say about it? But you know that they struggled or had pain points along the way. This phenomenon has a name, and it’s known as peak–end rule.

What is the peak-end rule?

Peak-end rule is a phenomenon where people judge an experience largely based on how they felt at its peak. The peak is the most intense moment. In other words, they forget about all of the feelings and emotions they were experience throughout the entire event. And thy seem to just “remember” how they felt at the peak, whether that is good or bad. This model dictates that an event is not judged by the entirety of an experience, but by prototypical moments (or snapshots) as a result of the representativeness heuristic, according to Wikipedia.

Why does it happen?

The peak-end rule tends to happen more on emotional events, even though people are not usually aware of their motional involvement at the time.  Also, people tend to remember how things turned out overall. If they had final success in the process, then their memory is going to be more positive and they tend to forget about the struggles they had along the journey. People just tend to think more positively of themselves when they have accomplished something, and therefore forget the negative aspects. One way to think about this is, if people think too much about it, and focus on the pain they went through, then they are likely to feel that pain again. So perhaps this is a instinctive defense mechanism? Without obtaining a psychology degree, I will leave that question open for debate.

How can you avoid it in your research?

The best way I can think of avoiding the peak-end bias is to observe participants in real time instead of relying on their account of it after the fact. This is why ethnographic research is so important in User Experience design. People are not even aware of some of the actions they perform. But if you are there to observe them in person, you discover all sorts of nuggets in behavior the user might not be aware to share. When you observe a participant, you see things like pain points, struggles, repetition, redundancy, mistakes, hacks, work arounds, cheating, confusion and all sorts of gold nuggets of user behavior.

I have seen it time and time again, a participant is trying to complete a task, and the software or website they are using does not perform as expected. The participant is frustrated. Maybe she expresses a slight sigh in displeasuer. Maybe she even tries to accomplish the task in a different way. Maybe she concedes and relies on the “hack” she has created as a work around. When confronted on an obvious frustration, she makes comments like:

• Oh what to you mean? Did I make a face? I didn’t even notice.
• I always have to do this.
• It’s no big deal, it’s just part of the job.

These comments are a tell-tale sign of actions that would likely not be reported in an interview after the fact.

The bottom line: Get out of the building and observe your user first hand. You will get much more context witnessing them in their environment rather than just “taking their word for it.” Observation is king!