“I confess that so far, Watson, I had been disappointed in my investigation. I had reckoned upon solving the matter when once I had found the place referred to in the Ritual; but now I was there, and was apparently as far as ever from knowing what it was which the family had concealed with such elaborate precautions.”
Doyle, C. (1922). The Musgrave Ritual. In The Complete Sherlock Holmes (p. 395). Garden City, New York: Doubleday & Company.
Imagine yourself walking up a mountain, you are exhausted and the sun is burning down upon you. As you look up, you see a leveling off of the path and the sky behind it is devoid of more mountain. You climb the crest hoping at last to be able to look out at the view you have worked hard to achieve, only to find that this summit is a red haring. More trail continues much further up the mountain. These tend to be the most frustrating challenges, those that fool you into thinking you are finished and then demoralize you by showing the insignificance of what you have accomplished. Are you content with where you have come so far, or do you desire more? It is almost a challenge, a taunt. These are the hardest puzzles not just for their length, but for the frustration that they bring as more questions are raised when one is solved.
My Common Place 