This shows the lifespan of the light source. Beamers need to have their lamps (light source) replaced every now and then.
Audible noise is the noise that a device produces while in operation. Reduced audible noise improves quality.
How much power the device consumes when it's switched on.
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.
Volume is the quantity of three-dimensional space enclosed by the product's chassis or, in simpler terms, the space the product occupies.