In , a man named Abraham Wald sat in a room with maps and charts. The United States military wanted to protect its planes. The planes were returning from battle with holes in the metal. The military looked at the holes. The holes were in the wings. The holes were in the tail.
The military wanted to put armor on the wings and the tail. Wald told them they were wrong. He said the holes showed where a plane could be hit and still fly home. He said the armor belonged where the holes were not. The planes that were hit in the engine did not return. Nobody saw those holes.
Red dots: Visible holes in surviving planes. Dark block: Where the armor actually belongs.
This is a mistake in thinking. We call it survivorship bias. We look at what is in front of us. We do not look at what is missing.
The Ghost in the Machine
I think about Wald when I look at a surgical schedule. A schedule is a piece of paper. It has names and times. It has numbers for grafts. It has been the same since . The schedule says a case of 1500 grafts takes six hours. The schedule says a case of 2000 grafts takes eight hours.
For , the clinic has used these numbers. For , the cases have run late. The staff stays late. The patients wait in the lobby. The surgeons feel the rush. Everyone says the case was difficult. They say the donor area was tight. They say the bleeding was heavy. They say these things every day.
They treat the overrun like a surprise. A surprise that happens every Tuesday is not a surprise. It is a data point. The template is a ghost. It exists in the computer. It exists in the mind of the manager. It does not exist in the operating room.
I stopped believing the template last year. I started looking for the holes where the planes did not return.
The Optimism Trap
Estimation is a psychological trap. Experts are the worst at it. This is a fact of human nature. We ask a surgeon how long a surgery takes. The surgeon thinks of a perfect day. The surgeon thinks of a perfect patient. The surgeon remembers the time they finished early. They do not remember the time they finished at nine in the evening.
The consistent error in expert estimation: For every three hours promised, the patient spends four in the chair.
In clinical studies of time management, the data is clear. If an expert says a task takes 60 minutes, the task usually takes 82 minutes. This is a consistent error. In plain terms, for every three hours the expert promises, the patient spends four hours in the chair. This is not a lie. It is optimism.
Optimism is good for morale. Optimism is bad for a schedule.
The Precision of Harley Street
I spent the morning counting. I did not count grafts. I counted the tiles on the ceiling. There are 24 tiles in the row. They are white. They have small grey specks. The specks are arranged in a pattern. I find the pattern boring. I find the pattern comforting. The ceiling does not change. The ceiling does not have an opinion on time. I looked at the ceiling and realized I hate data. I also realized I need data. This is a contradiction. I do not explain it.
The clinic is at 134 Harley Street. It is a quiet building. A surgeon from this
leads the consultation there. The surgeon looks at the scalp. The surgeon uses a lens. The lens shows the hair follicles. The surgeon counts the follicles. The surgeon checks the density.
This is the donor area. The donor area is the engine of the plane. If the donor area is difficult, the surgery slows down. The surgeon knows this during the consultation.
The surgeon is the same person who will do the surgery. This is a good system. It is better than a system where a salesman does the talk and a stranger does the walk. But even the best surgeon follows the template.
Predictable Variables
The template uses graft bands. Band A is small. Band B is medium. Band C is large. The template gives each band a block of time. It does not matter if the patient is twenty years old or sixty. It does not matter if the hair is straight or curly. It does not matter if the skin is soft or tough.
The template only sees the number of grafts. This is a mistake. The number of grafts is a result. The extraction is the process.
The process involves tools. The clinic uses the WAW DUO system. It uses the UGraft Zeus system. These are good tools. They help with graft integrity. They help with different hair types. The surgeon sits on a stool. The surgeon holds the handpiece. The handpiece has a punch. The punch is small. It is less than one millimeter wide.
The surgeon presses a pedal. The punch rotates. The punch enters the skin. The surgeon feels the resistance. The surgeon pulls the graft. This takes a few seconds. Then the surgeon does it again. They do it 2000 times.
If the skin is tough, each graft takes one extra second. One second is nothing. One second is the blink of an eye. But 2000 seconds is 33 minutes. If the donor area is tight, the surgeon moves slower. They must be careful. If they move too fast, they damage the hair. If they take two extra seconds per graft, the case runs late by an hour. The template does not know about seconds. The template only knows about the averages.
The Systematic Lie
Nobody has checked the finish times. The data is in the system. The computer knows when the lights go out. The computer knows when the last graft was placed. But nobody asks the computer for the truth. The managers look at the schedule. They see the overrun. They blame the patient. They say the patient had “difficult tissue.”
This is a way to avoid blaming the template. If you blame the template, you have to change the template. If you change the template, you can fit fewer patients in a week. If you fit fewer patients, the revenue drops. So the bias persists. It is a systematic lie that keeps the lights on.
We see this in other places. We see it in construction. A bridge is supposed to take . It takes . We see it in software. An app is supposed to take . It takes . The people making the estimates are not stupid. They are competent. They are experts. But they are looking at the wings of the planes that came back. They are not looking at the engines of the ones that crashed.
The 25% Solution
At Westminster Medical Group®, the surgeon leads the way. This is important. The person who assesses the donor area knows the truth of the skin. They know the depth of the root. They know if the hair is fragile. They have the information to fix the schedule. But they are human. They want to be efficient. They want to be fast. They tell themselves they can make up the time. They cannot make up the time. Time is a physical limit.
Adding this buffer to every schedule allows the stress to evaporate and the patient to wait no longer.
The fix is boring. The fix is a spreadsheet. You write down the estimate. You write down the actual finish time. You do this for a year. You do not judge the surgeon. You do not punish the staff. You just look at the numbers. You will find a gap. The gap is the “optimism tax.” In most clinics, the tax is 25%. If you add 25% to every schedule, the stress goes away.
The patient does not wait. The staff goes home for dinner. The surgeon does not rush the last 200 grafts. But nobody wants to do the boring work. It is more exciting to call a case “difficult.” It makes the surgeon feel like a hero. It makes the struggle feel like an accident. An accident is an act of god. A bad template is an act of management.
Armor in the Engine
I look at my hands. They are steady. I am not a surgeon. I build dollhouses. I understand scale. If I miscalculate the size of a door by one millimeter, the house looks wrong. If I do that times, the house is a failure. Precision matters in small things. A hair transplant is a collection of small things. It is thousands of tiny movements. Each movement takes time.
The information exists. It is sitting in the software. It is sitting in the paper files. It has never been asked a question. We live in a world of big data, but we ignore the small data in our own drawers. We repeat the same Tuesday every week for . We call it a career. I call it a refusal to look at the engine.
The template should be burned. A new template should be built from the actual finish times of . It would be a shorter schedule. It would be a more honest schedule. It would recognize that some donor areas are not “difficult surprises” but “predictable variables.”
Until then, the clock will keep running. The patients will keep waiting. And the experts will keep wondering why the day got away from them again.
I am going to stop counting the ceiling tiles now. I have reached the end of the row. There are no more holes to find here. The real holes are in the schedule. They are waiting for someone to put armor on them. The armor is the truth. The truth is usually longer than the estimate.