Take a look at Maslow’s Hierarchy of Needs; the lower levels of the pyramid consist of the things that are needed to sustain life. As you move up in the pyramid the needs are more social and psychological.
The hierarchy exhibits how a person first focuses on the most basic needs and once those are filled they then focus on the higher level needs. In our society we have pretty much filled the first two levels (physiological and safety) and most of us have filled the psychological needs (love and belonging).
The path taken to fill the lower level needs was to make more money and buy things to fill these needs. We would buy better food and better homes in better locations to meet the physiological and safety needs. Then to meet the social needs we would buy things that would attract others like nice cars, more fancy homes, etc.
Now many people have all of those things. They have enough food, a safe place to live, and many strong relationships.
The next step in the pyramid is self actualization. This comes in the form of a meaningful life, meaningful work, living up to your potential, making a difference in the world, and a whole list of other options. The problem comes in when we try to buy things to fill this need. Buying more and better stuff was part of the lower levels of the pyramid but it is going to be very difficult to buy something to increase your self actualization.
Many people do not realize they have all of their lower needs met; they just have a feeling of something missing. If we felt something was missing, in the past, we would buy something to fill it. To add to that way of thinking, our society tells us that we need to strive to get the better paying job, promotion, etc. So we buy and get promotions to continue the buying all trying to fill that missing piece. This is why we we end up with so much stuff and working so much that we do not get to spend time with our families (maybe this is also taking away from our belonging need) and the joy is absent in many lives.
In other words, we trying to fill the higher level needs the same way we filled the lower level needs (square peg in round hole).