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.
Edit 20 It’s been a week since this post and a lot of people are still reaching out to me with questions which is fine. I have had a few different people reach out to me to help make YouTube videos based off this guide and more info in BFA which I’m more than willing to do. Whoever gets the videos up first I will link them here for you guys to enjoy.