I made this suggestion to a SparkFriend who was having trouble staying on track. Whenever she noticed a loss on the scale, she became a little lax in her diet. She would then gain some back.
My suggestion: Tape a note with your goal weight on your scale. When you get on the scale, even if you lost weight you'll know you haven't yet reached your goal. This will motivate you to keep working toward reaching your goal, yet you'll still feel a sense of accomplishment for having a loss some!