To improve its smell and its wearability.

Yes, it is a noun. It is the noun form of the adjective "wearable."

Bonded leather is basically scrap leather and other materials (could be vinyl, split hides, textiles and who knows what) combined and manufactured with chemicals to produce bonded leather. Top grain leather, which is the most popular leather available today, at a relatively low cost and just a bit more than bonded leather, will hold up better, give a nicer touch, and outlast bonded leather.

This brand seems to be designed with an emphasis on comfort and wearability. They are cetrainly a premium label with many versions custom fit to the wearer and they will therefore command a higher retail price.

Bonded leathers are produced from scarp/trmmings, dust particle of natural leather. Because it produced from the trimmings and dust(shaving dust, ie. leather need to shave to get proper thickness) it need some cementing substances. These cementing substances are mainly various polymers and resins as well some other property enhancing chemicals such as silicones, rubbers, softeners, and colorants.

During finishing or coating process for esthetics and appearance these are coated with pigments and other auxiliaries such as urethanes, resins, silicones. Some articles also use transfer film with adhesives.

Natural leather is from outer coverings of animals( hides/Skins), it has natural grain structure. During processing it use tanning materials (inorganic or Organic), softening agents (Natural Oils, Synthetic oils, waxes, silicone etc), colorants,

During finishing it can be kept natural or pigmented finished, as well as transfer film.

Now to answer your question, system has been developed to bring the bonded leather feeling and some properties to match the Natural Leather.

Natural leather remain better in wearability, as natural has better breatability, and softness, streachability, etc.