A favorite scene from Alice in Wonderland is the passage where Alice asks the Cheshire cat for directions:

• “Would you tell me, please, which way I ought to go from here?”
• “That depends a good deal on where you want to get to,” said the Cat.
• “I don’t much care where—” said Alice.
• “Then it doesn’t matter which way you go,” said the Cat.
• “—so long as I get somewhere,” Alice added as an explanation.
• “Oh, you’re sure to do that,” said the Cat, “if you only walk long enough.”

The Cheshire cat might have added that without some way of recognizing the destination, you can never tell whether you have walked long enough! The proper destination for a data mining project is the solution of a well-defined business problem.

Via | Wiley, Data Mining Techniques For Marketing Sales And Customer Support (2004)