To test self-discipline and delay gratification, four-year-olds were put in room alone with one marshmallow. They were told they could eat it now, but if they didn't eat it and waited, they would get another marshmallow when the woman returned.
Oh, the agony.
The original test conducted by psychologist Walter Mischel at Stanford University went on to analyse the kids later in life.
The researchers then followed the progress of each child into adolescence, and demonstrated that those with the ability to wait were better adjusted and more dependable.
While the industry focus is often placed on flashy bits happening on the surface, Contact Energy chief customer officer Vena Crawley says it's often the hard graft beneath the surface that makes the difference.