In addition, your adult learners don't see the rewards of their efforts as soon as they would expect, and giving them candy doesn't work as it works with children. (elearningindustry.com)
If they are hitting quota consistently but not seeing any reward for their work, they won't be hitting quota much longer. (inc.com)
Often I give up when things get difficult, or I can't see the reward of my efforts. (teressajane.com)