Three Tenths Over: The Cost of Poor Quality

Or: “I don’t fly in no helicopters”

The Inspector Who Didn’t Care

“You’re three tenths over,” said the inspector.

The machinist looked at the bearing ring destined for a helicopter. Just three tenth-thousandths of an inch outside specification. Barely measurable. He asked the inspector to check again.

“You’re three tenths over.”

“Come on,” said the machinist. “Cut me a break. You can pass these, can’t you?”

The inspector shrugged. “Sure, what the hell. I don’t ride in no helicopters.”

I wasn’t that inspector. But I worked alongside him in my youth, making ball and roller bearings—some cheap and clunky, others high-precision artifacts for high-stakes machinery. I choose to believe I was more conscientious than that inspector. I hope I was.

But my months of conscientious inspection probably mattered less than what I discovered one day when I looked closely at our blueprints.

The Error That Haunts Me

When the company changed the equipment used to measure the curved raceways of bearings, some time in the 1960s, something went wrong with our specifications. The new, high-tech meters measured not diameter but radius. The radius being half the diameter, the tolerance limits should also have been halved. They weren’t.

If a bearing race’s diameter was meant to be 1/2 inch ± 3/1000 of an inch, and an inspector measuring its radius found it at +3/1000 of an inch, he passed the bearing as conforming to specification. But the bearing didn’t conform. The diameter was 6/1000 of an inch over the nominal target.

The bearings in this story were of the ultra-precision sort, where tolerances weren’t measured in thousandths of an inch, but in tenths of that. And we were routinely approving bearings that were outside design specifications, believing they were within spec. If an inspector felt lenient and passed a bearing 3/10000 of an inch over maximum, that error, was double for the actual diameter.

I reported this to management. They were very silent about the issue during the short time before they moved me to another plant. They never told me whether I was right or wrong.

I’m glad I’ve never taken a ride in a helicopter.

Learning From Deming

Within a year or two, layoffs hit the bearing factory. I was fortunate to land at an auto parts manufacturer producing radiators and air conditioners. This was during the era when American industry was learning it had been trounced by Japan—not just because of exchange rates, but because the Japanese had learned lessons about quality that had never quite taken hold on this side of the Pacific.

American captains of industry learned through a television special called “If Japan Can, Why Can’t We?” They discovered that what the Japanese knew had been taught to them by an American: W. Edwards Deming. And so American industry scrambled to learn what Deming could teach.

We in the quality department were pulled from our regular duties to attend lectures on Deming’s 14 Points. We watched videos of crusty old Deming explaining why quality paid for itself, wasn’t a cost added to manufacture. I still remember his cadences: “Less scrap… (long pause) less rework… (long pause) less cost all around.”

I didn’t quite get it. But I got it enough to know that the management of my company got it even less than I did.

In my blue-collar world, I was used to being the smartest person in the room. Later, in Silicon Valley and the software industry, I still held my own. Though a poet and theater major, I learned to code and did well enough to be promoted to my level of incompetence: management. I knew computers but I didn’t understand business.

Bad News About My Brain

Impatient with myself, I enrolled at the MIT Sloan School of Management.

At MIT, I faced a rude awakening. For the first time in my life, I was in a context where my brain was genuinely mediocre. Worse, most of my classmates had levels of experience I hadn’t dreamt of. I was taking managerial accounting with accountants, cost accounting with finance executives, economics with consulting firm veterans.

I was pathetic.

But one thing struck me: quality was seldom mentioned at Sloan.

What MIT Didn’t Teach

There are a handful of quality pioneers—gurus who pioneered the 20th century quality revolution: Deming, Juran, Crosby, Feigenbaum, Ishikawa, Taguchi, Ohno. Of these, only one was mentioned in any of my classes: Taguchi. And even then, not for his central contribution to quality.

In an operations class, we learned the Taguchi method of experiment design. The lesson involved making planned variations on the classic paper airplane. It was enjoyable, instructive even. One of my most brilliant classmates—a man named Dan DiSano, built a plane that sank like a stone. I tried not to join the others in smirking, but I had to hide my face behind my hand. Dan had outshone me in every possible way—but now I built a plane that flew a few yards and looked down on the wreckage of his.

But we didn’t learn Taguchi’s loss function, his most important contribution. Years later, writing for the American Society for Quality, I returned to Deming’s work and was reminded of Taguchi’s central insight:

At America’s premier business school, future business leaders learned strategy, operations, finance, accounting. But the cost to society of poor quality? That wasn’t in the curriculum.

Massachusetts Avenue, winter

I know the exact date not because I kept careful diary entries—business school kept me in a state of constant exhaustion—but because you can still look it up.

Next morning I was scheduled for a job interview in Washington, D.C. I was driving from my home in Arlington to Logan Airport. I took Massachusetts Avenue because it runs right by MIT and I knew it well. It was a poor choice that day, though I had no way of knowing.

Long before I reached campus, traffic stopped completely. I sat in that unmoving line for a long time until I realized this was significant enough to make the news. Flipping through radio stations, I caught just a few words: something had crashed into the Harvard Sailing Pavilion.

But that couldn’t be the problem— surely the Harvard Sailing Pavilion would be adjacent to that school’s campus, and I’d already driven past Harvard.

But no.

Only over time did I piece together what happened. The Harvard Sailing Pavilion sits directly across Massachusetts Avenue from the Sloan building where I’d spent the past year studying business. It was close to the street, on the bank of the Charles River.

It wasn’t a car, truck or bus that lost control on Mass Ave and crashed into the boathouse.

I haven’t told you when I was at Sloan. But if you were curious, you could learn the exact date of my long drive to the airport. You’d only have to Google:

Harvard sailing pavilion crash

…and one other word:

helicopter.

The Cost to Society

Witnesses said that the rotor had completely stopped turning when it struck the boathouse.

Taguchi said that quality is the measure of the cost to society associated with a product.

Two state troopers, along with two other human beings, lost their lives that day. Four people killed.

I didn’t know if bearing failures caused that crash. The investigation may have identified other causes entirely. But I know what I discovered in that bearing factory. I know about the inspector who passed parts for helicopters because he didn’t ride in them. I know that tolerances that should have been halved weren’t. I know that American business schools taught future executives everything except the cost to society when quality fails.

And I know why I’ve never flown in a helicopter.

Quality isn’t an abstract concept taught in lectures about 14 Points or loss functions. Quality isn’t statistical process control or Taguchi methods or paper airplane experiments.

Quality is the difference between four people going home to their families and four people dying on the bank of the Charles River.

That’s why I’m obsessed with quality.

And that’s why the culture of quality—not just the tools, not just the methods, but the culture—matters more than anything we learned at business school.