One day, an expert in time management was speaking to a group of business students and, to drive home a point, used an illustration those students will never forget. You won't either. As he stood in front of the group of high-powered overachievers, he said, "Okay, time for a quiz." He then pulled out a one-gallon, 'wide-mouth' mason jar and set it on the table in front of him. Then he produced about a dozen fist sized rocks and carefully placed them, one by one, into the jar. When the jar was filled to the top and no more rocks would fit inside, he asked, "Is this jar full?" Everyone in the class said, "Yes." Then he said, "Really?" He reached under the table and pulled out a bucket of gravel. Then he dumped some gravel in and shook the jar, causing pieces of gravel to work themselves down into the spaces between the big rocks. Then he asked the group once more, "Is this jar full?" By this time the class was on to him. "