Most of the time you spend leveling will involve questing and slaying monsters, but there’s also a lot of travel. Travel earns you little experience (you do gain a bit for discovering new areas), so it’s wise to keep travel to a minimum. The new level scaling system, which scales zones to your level within a preset range, helps with that. You can choose what zones you want to experience and stick with them until you finish their quests.
Ever since Blizzard introduced the WoW Token, World of Warcraft's in-game gold has had a more direct comparison to real-world markets. WoW tokens can be bought with real money ($20) and then sold on the World of Warcraft auction house for gold. Players who buy a WoW token with gold get to redeem it for $15 on their Blizzard account, which is equal to one month of WoW playtime.
In particular, between 2014 and 2016, it was possible for dedicated players to generate quantities of gold that were previously impossible to obtain, and have not been possible to obtain since. The Warlords of Draenor expansion was the first time the game included nonplayer character followers that players could send on missions to collect resources, items and other useful stuff, including gold.
As the gold price of a $20 token falls, more people with gold are willing to convert it into tokens, and fewer people with money are willing to buy gold at that rate. As the gold price rises, the value of the token begins to exceed the value of the time spent accumulating the gold for some market participants and they stop selling their gold. Meanwhile, other people with cash are enticed to enter the market because of the high amount of gold they can get for their tokens.