With Janice, she is not anywhere near the field of work she enjoys. She needs to make a big shift to reduce her depression. Alternatively, Max mainly needs to find a project he enjoys more. He is surrounded by creative people, which makes his depression more mild, and he's on the right track with a job in graphic design. He only needs to make a minor adjustment to reduce his depression.
Similarly, a person might need to do some examination of their symptoms to figure out what part of their life is causing their depression. For example, if you are experiencing a loss of interest in your group of friends but have great relationships with your partner and family, you might need to examine your friendships and the area of your life relating to them.
The nature of your symptoms will give you some clues on what you need to change. Examining the areas of your life where your symptoms are most prominent can help you figure out which areas need your attention most and if change will be required in order to improve your mood.