Something that is generally widely touted in terms of improving your finances is the idea of “passive” income. With that we are talking about income that does not require you to spend any effort to obtain it.
Can you really find passive income?
Even in the real world there are very few sources of passive income. Some forms of investments may be considered almost purely passive. In WoW this is even harder as there are no ways to make gold that requires no activity.
In WoW we would rather be looking for income sources with very small amounts of time needed to profit from them.
The mission table
The Legion and WoD mission tables represents the most passive gold making the game has ever seen. Particularly the Legion variant with the ability to complete missions on your mobile phone.
With a large enough alt army you could easily make a token a month mostly playing the game from the phone. The only bottleneck would be the order hall resources, which could limit you depending on how you play.
Front loading effort
To profit from the mission table optimally you would front load your effort. You needed several level 110s, which takes time as well as enough order hall resources to fuel yourself.
The closest you can get to passive income in WoW is similar methods where you can frontload the effort and then maintain your income with very little effort.
Passive income in BfA
Sadly there aren’t any methods that are on the level of gold missions in BfA. The most widespread low effort methods include utilizing the Daily cooldowns from old world alchemy to get some profit, and the gold missions in BfA, which give very little.
You could make the case that some crafting markets approach passive gold making such as sky golems and other luxury mounts, but it is generally on a much lower level.
Gold making requires some effort
Sadly all the good gold making methods in BfA do require continuous efforts of some sort. Whether it is scanning the AH, farming or crafting they all require you to spend time actively doing it.