This is where you want to look at the construction of the wool carpet as well as the carpet fiber. Wool fibers are resistant to compression due to the physical nature of the fiber’s “natural crimp”. It has millions of coiled molecules, rather than the artificially induced sinoidal waves which exist in man-made fibers. It will not “ugly out”, but age gracefully. For heavy traffic areas, you want to look for a dense pile (you don’t want to be able to easily see, or feel the backing of the carpet through the fiber). Shorter pile heights (those under ½”) perform better in heavy traffic areas like entries, stairs, hallways, and playrooms). In a cut pile, a tight twist is always more durable than a looser twist and with Berbers…. the smaller tighter loops will be more durable than the larger looser loop. The best performing cut pile style is the Frieze, it consists of many tightly twisted yarns.