The primary thing when you take a sword in your hands is your intention to cut the enemy, whatever the means. Whenever you parry, hit, spring, strike or touch the enemy’s cutting sword, you must cut the enemy in the same movement. It is essential to attain this. If you think only of hitting, springing, striking or touching the enemy, you will not be able actually to cut him.
The McNamara fallacy, named for Robert McNamara, the US Secretary of Defense from 1961 to 1968, involves making a decision based solely on quantitative observations (or metrics) and ignoring all others. The reason given is often that these other observations cannot be proven.
The fallacy refers to McNamara's belief as to what led the United States to defeat in the Vietnam War—specifically, his quantification of success in the war (e.g., in terms of enemy body count), ignoring other variables.
Who advocates in the requirements process for the product itself—its conceptual integrity, its efficiency, its economy, it’s robustness? Often, no one. As often, an architect or engineer who can offer only opinion based on taste and instinct, unbuttressed as yet by facts. For in a classical Waterfall Model product process, requirements are set before design is begun.
The result, of course, is a grossly obese set of requirements, the union of many wish lists, assembled without constraints. Usually, the list is neither prioritized nor weighted. The social forces in the committee forbid the painful conflicts occasioned by even weighting, much less prioritizing.