There are debates about whether the marshmallow task really measures the ability to delay gratification or is it just an index of socioeconomic status. The research that has been done over the last couple of decades is that interestingly, the trick to delaying gratification is to bring the gratification forward in time. Most people find ways to either have anticipatory utility or for eating an exercise.
What’s the difference between people who preserve special things and people who devour them right away? Why do we love to binge-watch? And did Adam really eat an apple?