The Marshmallow Test
I'm reading a book called "How Children Succeed" and I'm taken by it. If there is one message from the book, it’s that teaching grit, curiosity, focus, optimism and overall character traits in children is possible - and leads to them becoming more successful. It also makes the point that focus and discipline often trump IQ and academic credentials in life. As an entrepreneur and an employer, this rings true to me on every level. 
Perhaps one of the most intriguing chapters in the book discusses the traits of self control, willpower and the "Marshmallow Test." At a nursery school in California, a researcher brought each four-year-old into a small room, sat the child at a desk and offered a treat, such as a marshmallow. On the desk was a bell. The researcher told the child she was going to leave the room and the child could eat the marshmallow when she returned. Then she offered a choice; if the child wanted to eat the marshmallow, he or she just needed to ring the bell, the researcher would return and the child could have the marshmallow. But if the child waited until the researcher returned on her own, he or she would get two marshmallows.
Long story short, the kids that had the ability to delay gratification did better academically despite their IQ. Children who were able to wait for 15 minutes for their treat had SAT scores (later in life) that were, on average, 210 points higher than those of children who rang the bell in 30 seconds.
The marshmallow test brings me back to my own childhood experiences. My mom used to reward us with quarters for good deeds. My brother James had a choice of using the quarter immediately to ride the electronic pony at the mall or to save his quarters for a larger reward down the line. He always saved those quarters (and that public school kid from Connecticut got himself into Yale and went on to do great things). In a world where instant gratification is the goal, learning to work for something over time and delay gratification is just one of many character traits essential for success.
At Prosek Partners we often ask recruits if they've had a "dirty job," such as bussing tables, riding the trash truck, bagging groceries or working in the steel mill (yes, one of our firm’s partners did that!) Why? Because we've found that having done a “dirty job” correlates with having a good work ethic, gratitude, empathy for the everyman and overall conscientiousness. But what it really comes down to is the correlation with character. 