Odd number groupings, especially groups of three, are preferred in modern interior design because they create a natural sense of balance and harmony that feels pleasing to the eye. Unlike even-number groupings, odd numbers avoid symmetry that can feel dull or forced. Three objects arranged at different heights or sizes introduce rhythm and focus in a room, making spaces feel curated but relaxed. Using the rule of three allows rooms to appear thoughtfully styled without visual clutter or stiffness, promoting calmness and intentionality in everyday living spaces.