Deferred gratification

Deferred gratification, delayed gratification, or emotional intelligence is the ability of a person to wait for things they want. This trait is critical for life success. Those who lack this trait are said to need instant gratification and suffer from poor impulse control, and often become criminals, as they are unwilling to work and wait for their paycheck.

It has also been said that those with poor impulse control suffer from "weak ego boundaries"; which comes from Sigmund Freud's theory of personality where the id is the pleasure principle, the superego is the morality or parent principle, and the ego is the reality principle. The ego's job is to satisfy the needs of the id while being conscientious of other people's needs. This is why people who are impulsive are said to have "weak ego boundaries".

Experiments
The marshmallow experiment is a famous test of this concept by Daniel Goleman, an American psychologist. In the 1960's he tested a group of four-year olds, by giving them a marshmallow and promising them more, if they could wait 20 minutes before eating the first one. Some children could wait and others could not. He then followed the progress of each child into adulthood, and demonstrated that those with the ability to wait were more successful in life than those who couldn't.