For example, we have over-relied on material possessions to feel good. Of course, we can Enhance the experience of a mental state by modifying the environment. However, we have literally curated our individual environments and the bigger planetarial environment in our quest to feel good (i.e., comfort and convenience).
By doing so we have forgotten that feeling good does not require an external environment to happen. You can feel good right now by just going out of the door, breathing, and just being.