" Csikszentmihalyi told me, “People seem to concentrate best when the demands on them are a bit greater than usual, and they are able to give more than usual. If there is too little demand on them, people are bored. If there is too much for them to handle, they get anxious. Flow occurs in that delicate zone between boredom and anxiety. "

― Daniel Goleman , Emotional Intelligence: Why It Can Matter More Than IQ