https://telegra.ph/Why-Item-Up....grades-Isnt-A-Topic-
The Item Upgrader in World of Warcraft The War Within introduced two gear upgrade currencies: Valorstones and Harbinger Crests. These can be exchanged at the NPCs who upgrade items, Cuzolth and Vaskarn. Each item may be upgraded to its maximum level only once for a slot. After that upgrades to that slot will be cheaper. The pity system that was introduced in The War Within, also reduces the extreme variance in upgrades. Upgrades Upgrades are components that improve performance or add new functionality