World of Warcraft Item Upgrades
Upgrades to an item are a way to boost the stats of an item. Based on the type of upgrade it could raise an item's Mark level or Rarity and boost additional stats.
Each item comes with a track for upgrading it. Each upgrade increases the cost of the following one by a specific amount.
Item Level
The value of an item's stats base increases when it is upgraded. The value is the sum of the perks that are leveled up (attack magic attack and defense). Upgrades can be expensive, depending on the person you hire and what you decide to do. This is due to the sheer number of perks that have to be modified to upgrade an item.
Item level is a popular measure of power, and is visible on all item tooltips. It also serves to limit the amount of PvP gear players can use since PvP is not available at a lower level. Players can view their average level of items on their character sheet.
The level of an item can help players evaluate the strength of equipment when deciding to purchase or sell. It's a good indicator of the quality of an item and how much damage it is capable of causing. Comparing items in the inventory of a vendor can be done using the item level.
On your PC, you can see the level of the item by pressing ALT or using the left stick on XB1 or PS4. This will display the complete item description, including its value. You can also find it by hovering over an item and typing /itemlevel into chat.
There are a few theories on how the item level calculation is made. One theory is that the item level is a number derived from a formula that determines how much an item's stats are worth. It takes into account the fact that different perks have different values and that gems in sockets add to the overall value of the item. This can result in a calculated item's ilvl that is typically very close to Blizzard's real level of the item.
It's not the only factor that affects the value of an item. The level of the area where the item was dropped can change its stats. For instance it can add a level to the item's haste, or crit rating. This means that items that drop at higher levels will have more the ilvl than items from lower level instances.
Item Stats
The stats of an item can determine the fate of an item for players. The game uses them in many ways to encourage players not to limit themselves to one weapon and to motivate players to explore other weapons. The stat mods of an weapon increase the base stats. These stat mods are then boosted by a player's skill.
Upgrades to an item may increase the stats of an item. The cost of upgrades is determined by the rarity of the item. For example, a grey or white item can only be upgraded once, whereas an item with rare levels will be upgraded multiple times, at higher costs.
Affixes are a different method to change an item's stats. These are special stat boosts that can be added to an item by the player, and are available in all shapes and sizes. The affixes can do things like give the item additional damage, add a special capability to the item (such as reviving dead or decreasing the cooldowns), or make the item unique by giving an exclusive name to the item.
Presently, all affixes are able to be rerolled by selecting them from the upgrade window and pressing the green button with circles arrows. This will cost a certain amount of gold and other items. These can be used as upgrade gauges, as with other methods of rerolling.

Players can choose to upgrade an item by specific stats or reroll affixes. The possible stat ranges for an item are based on the item level, but every item is guaranteed to have at least 1 stat within that range, unless it is an exclusive item or a God roll from a raid boss.
Another thing that could be altered by introducing an option to upgrade the equipment without rolling the affixes or deciding which stats to boost. Like base equipment, it would have to be done per item and the item comparison interface would not display all the possible stats at once.
Item Luck
The Luck stat of a player can increase the probability of obtaining items as well as the properties spawned by loot and the strength of these properties. It does not, however directly impact damage or the ability to upgrade item s. It gives players the chance to upgrade their equipment earlier in the game. This is especially advantageous for early game runs, since players tend to prioritize the scaling of weapons and defenses over raw damage gains.
Luck can also increase the chance of upgrading items at the Blacksmith. This isn't to be confused with the Blacksmith's overall chances of upgrading, which increase with each item level. These can also be increased by using anti-materials such as the Scroll of Strength and a Jewel of Blessing.
Armor, shields and weapons come with an initial Luck value of 40. These items can be improved with golden ingots or spined leather (depending on their material type) for a further +40 luck or to increase the luck of the item to 140.
Moreover, certain items, such as the Hollow weapon, which is infused with Hollow, can be equipped to increase the damage dealt by any damage-dealing skill by 5%. These items are available from the shop or made using the correct ingredients.
Item Failure
Item upgrades are expensive and not every upgrade will be successful. However, there are some cash shop items which allow players to increase their success rate or prevent them from losing an item if the upgrade is unsuccessful.
When you upgrade an item the rate of success is displayed in the Honing UI. The percentage represents the likelihood of successful upgrading an item. This can be increased with Additional Materials or Special Materials. The probability of success can only be increased as high, and the probability that an upgrade will fail can't be greater than 100%..
The luck of an item may affect the effectiveness of an upgrade. All items have an average success rate of 25 percent and every item with Luck increases this chance by 5percent.
Note that item upgrades are rendered above the items in the inventory which means that enchantment glints and other effects can be masked by them. If you wish to disable the upgrade overlays, the config option decoration.renderUpgradeOverlays can be set to False in the Item Upgrader CORE client config.