Imagine you're at your favorite apparel store to shop. You find everything you want, some of which even fit you perfect, and some at a lower price. However, a bad experience at the end ruins it: waiting to pay, your card doesn't go through, or the cashier is extremely rude.
People tend to evaluate an experience mainly based on the peak moments of an emotion (positive or negative) as well as the final emotion. In other words, by applying a shortcut, they isolate certain moments and don't rely on the entirety of the experience. Moreover, the tendency to favor the recording not of the entirety of an experience, but how it was at its peak and how it ended is called the peak-end rule.
Look at what Disney does in its parks. At the end of the day, it organizes a spectacular show for the grand finale, including a dazzling spectacle with explosive fireworks, lights, and wonderful music. This way, instead of customers remembering the long waits for rides, family arguments, and sore feet, they leave with the memory of a magical experience they'll want to return to again and again.
But how can a company leverage the peak-end rule?
The answer is rather obvious. To create a moment of excitement (e.g., like when the employee remembers what we bought last time), especially if it happens at the end, to create a memorable experience. Even if the rest of the experience was mediocre - of course, the opposite can also be true.
In the case of a restaurant, the food for a family might have been indifferent, but the waiter, who was extremely polite and particularly friendly with the kids, made the difference and created a positive experience. Conversely, the food might have been absolutely delicious and the waiter polite, but a bad experience (e.g. overcharge) could ruin the entire experience.
For this reason, many businesses try to positively close the experience with a "kind" gesture at the end (e.g., treat, gift, even a sincere apology). In many small hotels, a warm farewell from the owner, even a sincere "thank you for choosing us," might be enough to rectify any imperfections.
It's obvious that the peak-end rule can have exceptional results when applied to staff as well. For example, in many supermarkets, left overs shared among the staff.