Peak-end rule
We judge a past experience mostly by how it felt at its most intense moment and at its end. The average of all the other moments counts for much less.
In everyday life
A week-long vacation full of rain and delays is remembered fondly because of one amazing day and a perfect final evening.
A long, dull dinner party closed with a hilarious toast, and when friends ask how it went, you call it one of the best nights of the year.
Why your mind does this
We cannot hold every moment of an experience or every item in a list in mind. The brain keeps a few standout pieces, such as the most intense moment, the ending, or the first and last items, and lets them stand for the whole. This makes memories compact and quick to use.
How to spot it
Ask whether your rating of an experience reflects the whole thing or mostly its most intense or final moment.
How to counter it
When reviewing an experience, such as a trip, a job or a product, rate its beginning, middle and end separately before scoring the whole.
Same family: Key elements
SourcesKahneman et al. (1993)·Wikipedia