You Want To Challenge Yourself

"It’s also important when you set goals to make them difficult, while still being realistic. You want to challenge yourself and set the bar high, because challenges really get the motivational juices flowing, while avoiding goals that are more or less impossible. Remember that if you set the bar too low, you may achieve your goal but are unlikely to surpass it—most people tend to slack off once they’ve reached their original target. Nobody sets out with the goal of losing five pounds and ends up somehow losing twenty.

-- Heidi Grant Halvorson