Product design goes beyond mere enclosure; it communicates a product's functionality and utilitarian features. A product's appeal, appropriateness, and beauty act as pivotal links between consumers and their choices. This study delves into the quantification of the appropriateness feature in product aesthetics and its profound influence on human visual and cognitive processes. Examining a diverse array of beverage bottle silhouettes, our two-phase study, involving six experts and over 300 participants, brings forth compelling revelations. In phase I, the Frequency Match Ratio (FMR) analysis underscores consumers' adept understanding of function perception during the visual matching of specific silhouettes. Notable examples include the remarkable match ratios achieved for alcohol bottle silhouette P2 (94.71%) and carbonated drink bottle silhouette P5 (85.88%). Furthermore, phase-II, the eye-tracking results revealed several significant findings. Gender-related differences in pupil diameter were noted, with males showing distinct variations, potentially influenced by the robust shapes of alcohol bottles, and females displaying fluctuations, suggesting familiarity with certain bottle designs, particularly under more complex tasks. The fixation count, a metric of cognitive processing, identified areas of pronounced interest influenced by shape, curvature, and texture, with female participants exhibiting distinct fixation patterns emphasizing the role of shape and curvature in evoking emotional responses. Total Fixation Duration, a measure of visual attention, indicated that participants allocated substantial time to examining angular and deeply curved shapes, particularly focusing on elements like bottle necks, slant heights, and angular regions. The study's findings provide designers with insights into consumer preferences for perception of function (appropriateness) feature of product aesthetics, enabling the creation of products that align with both form and function. This approach can empower companies to enhance product aesthetics and gain a competitive advantage.
