When deciding, how something makes us feel weighs as much as its logic.
When a barista writes your name on the cup, it creates a small but real connection. The affect heuristic happens when we base a judgment or decision on the positive or negative feeling we associate with the situation, rather than on a cold analysis of pros and cons.
In 2011, Coca-Cola launched the "Share a Coke" campaign, printing people's names on bottles to encourage sharing them with loved ones. The campaign increased sales by 7%, with more than 250,000 personalized bottles sold in just three months after its launch in Australia. The emotional connection of sharing something with a loved one's name on it drove the result, without touching the price or the product.
Using our emotions as a guide is faster than evaluating every positive and negative aspect of a decision, and under time pressure or complex information, we tend to rely on that shortcut even more.
Source: Bateman, I., Dent, S., Peters, E., Slovic, P. & Starmer, C. (2007). The Affect Heuristic and the Attractiveness of Simple Gambles. J. Behav. Decis. Making, 20, 365-380.
A small, genuinely human detail (a name, a personalized message, a follow-up call) often moves the needle more than an extra discount, because it changes how the interaction feels, not just its cost.
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