This is the movie's key dialogue, because without the misery of his job (with its fluctuating sleep schedule and amoral cost calculations) The Narrator would not birth the alter-ego Tyler Durden:
"A new car built by my company leaves somewhere traveling at 60 mph. The rear differential locks up. The car crashes and burns with everyone trapped inside. Now, should we initiate a recall? Take the number of vehicles in the field: A. Multiply it by the probable rate of failure: B. Then multiply the result by the average out-of-court settlement: C. A times B times C equals X. If X is less than the cost of a recall, then we don't do one."The women he's talking to is horrified. Hers seems like the right response to "the formula" but it's not.
"Are there a lot of these kinds of accidents?"
"You wouldn't believe."
Even cars that are well designed and manufactured will have occasional dangerous flaws. Auto recalls can easily cost tens of millions of dollars. If you buy from a car company that performs a recall every time there's the slightest chance of a rear differential locking up, you have to pay for a share of all of those recalls. So there's a trade-off between safety and price: cars from recall-happy producers will cost you more (and possibly a lot more) but you'll be less inclined to die on the freeway. And the obverse.
As a consumer, you should want your car company to use some version of "the formula." All it is is a way to balance safety and price (which includes X, recalls, car production costs, etc.) on an industrial scale.
Still think the "formula" is a bad idea? In a crash two major safety factors are weight and size. This is because the severity of accelerations in the crash is what leads to injury, even if everyone stays in his seat and nothing ends up stabbing or crushing anyone. So if you crash into a big, unyielding tree while driving at 45 mph (assuming you stay in your seat) you only have the distance from the bumper to whatever element of the car the tree eventually ends up wedged against to go from 45 mph to 0 mph. The longer the hood, the more potential crumple zone and the greater the distance of deceleration. Now, this is complicated by a head-on collision with another car. In that case, a big and heavy car is a bonus. The heavy car will have more momentum, so it will push the light car backward (unlike the unyielding tree) meaning that it will decelerate more slowly. The light car driver will be toast.
So, if the safety/money trade-off of "the formula" is so inherently evil, everyone who's enraged at this corporate amorality and greed should never trade safety for money. So why do people buy their kids used $3000.00 Geo Metros instead of the $35,000.00 mid-size Acura TL?