The spotlight effect bias was first identified and named by researchers Thomas Gilovich and Victor Husted in their 1999 study published in the Journal of Personality and Social Psychology. Through a series of experiments, they found that individuals consistently overestimated how much others noticed and paid attention to their appearance and behaviors.

In one experiment, participants wore an embarrassing t-shirt and then estimated how many people would notice it. The results showed that the participants significantly overestimated the number of observers who would actually notice the t-shirt. This phenomenon was attributed to the spotlight effect, where individuals assume they are the focus of attention, even when they logically know that others are preoccupied with their own concerns.

The researchers proposed that the spotlight effect stems from a combination of factors, including the human tendency towards egocentric thinking, the vividness of our own experiences, and the availability heuristic, where we rely on easily accessible information to make judgments.

The spotlight effect can have significant implications for team dynamics. For instance, in meetings, we may assume that our ideas, comments, or mistakes are scrutinized more closely than they actually are. This can lead to hesitation in expressing our opinions or taking calculated risks.

If a designer presents an idea that receives criticism, we may assume that the feedback is a personal attack or a reflection of our capabilities, rather than objective feedback aimed at improving the overall product.

For engineers, the spotlight effect may manifest when we are hesitant to share our code, fearing judgment from our peers. This can result in siloed work, inefficiencies, and potential technical debt.