The Tibetan Terrier Standard says: 
"The Tibetan Terrier evolved over many centuries, surviving in Tibet’s extreme climate and difficult terrain. The breed developed a protective double coat, compact size, unique foot construction, and great agility. The Tibetan Terrier served as a steadfast, devoted companion in all of his owner’s endeavors."
  
"The dog with the correct foot and leg construction moves with elasticity and drive indicating that the dog is capable of great agility as well as endurance."