From the Human Givens approach:
All organisms, including humans, have different needs and if the needs are met pretty well, they will mature in a fully rounded way.
“Greed tends to dominate an individual or group when needs are not met in balance, and feeds the ubiquitous confusion between needs and wants. If our need for attention is not met, for example, we become attention seekers, which can become destructive to relationships. We can become greedy for comfort, turn to food and overeat and become lazy. We can be greedy for status, if status has been denied us in childhood and adolescence, and this can develop into an aggressive drive to dominate others in order to extract status through power.
“Any healthy human need, if unnurtured, can swell into a destructive want. In a mature society, the process of getting people’s needs met provides a natural rhythm of checks and balances to ensure no one becomes excessively greedy or cruel.
“But greed draws its strength from the fact that, in a fundamental way, like all basic emotions, it is directly linked to survival. Every living thing has to take from the environment around it to stay alive. This is why our greeds can become overwhelmingly powerful. Like all emotional states, a greed for something, whatever it is, focuses and locks our attention so we are unable to see the bigger picture — what’s really happening…”