Some men prefer shorter women because they associate a smaller height with certain physical proportions and relationship dynamics they personally find attractive. Height preferences vary enormously from person to person, but differences in height can influence first impressions and physical attraction.
One reason is simply contrast. A man who is considerably taller than his partner may enjoy the noticeable height difference when standing together, hugging, or walking side by side. For some couples, that contrast creates a sense of physical compatibility they particularly enjoy.
Body proportions can also appear different on shorter women. Curves, legs, waistlines, and overall silhouettes may look more compact depending on someone’s individual build. These visual differences can influence attraction, although they have far more to do with individual body proportions than height alone.
Personality, however, cannot be predicted from someone’s height. Shorter women aren’t automatically more affectionate, feminine, confident, or compatible than taller women. Those characteristics depend on the individual, which explains why plenty of men have no height preference at all—or specifically prefer taller partners.
So the answer behind the claim is largely physical preference and the appeal of a noticeable height difference. There is no universal rule that men prefer short women, but for those who do, appearance, proportions, and the physical contrast between partners can all contribute to that attraction.