On keeping your own score…

“People and institutions cannot keep their own score accurately. Metrics soon become targets and then pitches, and are thereby gamed, corrupted, misreported, fudged…

Examples: premature revenue recognition, Libor rates, beating the quarterly forecast by a single penny, terrorist attacks prevented, Weapons of Mass Destruction, number of Twitter followers, all body counts (crowd sizes, civilians blown up). Sometimes call the Principle of Lake Woebegone, where all children are above average.”

– Edward Tufte