Interpupillary distance (IPD) is the distance between the center of your eyes. Without adjustable IPD, the lenses of a VR headset may not line up with your pupils, which can result in eye strain and nausea.
We consider a lower weight better because lighter devices are more comfortable to carry. A lower weight is also an advantage for home appliances, as it makes transportation easier, and for many other types of products.
We consider a thinner chassis better because it makes the product more compact and portable. Thinness is a feature highlighted by many manufacturers of mobile devices, but it is essential for a wide range of products.
The height represents the vertical dimension of the product. We consider a smaller height better because it assures easy maneuverability.
Volume is the quantity of three-dimensional space enclosed by the product's chassis or, in simpler terms, the space the product occupies.
The width represents the horizontal dimension of the product. We consider a smaller width better because it assures easy maneuverability.