Chronic depression doesn't usually have a "cause" that you can fix without some form of treatment. It happens that these meds often do remove the extreme effects of depression and allow you to focus on other problems.
Is that true or your guess?
You can't have first-hand experience of "usually" where that applies to multiple people.
You’re as capable of typing “causes of chronic depression” into a search bar as anyone else. The fact that you don’t do that indicates you don’t want to contribute. You just want to be argumentative.