MFA Thesis Series 1: Why Is It So Hard to Find Shoes That Actually Fit?

A thesis is different from a studio project — and the difference, for me, was research. Not a few interviews or a quick survey, but nearly two years of literature review, factory visits, practitioner conversations, and consumer fieldwork. Most of that process gets compressed into a few slides in a portfolio. I always thought that was a shame. So I wanted to tell the full story here.

Here are the blog posts of the stories behind my MFA Thesis. I hope you enjoy them.

Where It All Started: A "Rebellious" Question

During my years studying in the United States, I rarely bought shoes here. Most of my shoes were purchased during trips back to China. Not because I had any particular loyalty to Chinese brands, but simply because I could almost never find shoes that fit my feet in American stores. The size would be right, but my instep wouldn't fit. The style would be perfect, but the heel would gap. And when I finally found a pair that didn't crush my instep or squeeze my toes, the arch support would feel completely off.

This had been a persistent frustration in my daily life — one I quietly put up with, working around it as best I could. It wasn't until I started working on my MFA thesis that I gradually came to realize: this wasn't my problem. It was a problem with the entire system. And that system, it turned out, was far more broken than I'd imagined.

My thesis began with a challenge to one of industrial design's most fundamental assumptions.

From the moment I started studying industrial design, I was taught that every product must be designed with mass production in mind — accounting for constraints in manufacturing processes, materials, tooling, and equipment. Designers work within this framework, shaping their ideas to ensure they can actually be made. And of course, this is a worthwhile framework. Mass production makes good products affordable and accessible, raising the quality of everyday life for millions of people. That's genuinely remarkable.

But is this model perfect? Does it ever break down? Are there areas where mass production creates problems rather than solving them?

Footwear, I discovered, was one of the most telling answers.

Mass Production's Logic — and Its Key Tools

The great achievement of mass production was solving an age-old problem: how do you give people better products for less money and effort?

Before mass production, almost everything was made by hand. Quality depended on the individual craftsperson's skill, and prices put most goods out of reach for ordinary people. Mass production broke through this with standardization and economies of scale: the same blueprint, the same molds, the same assembly line — producing thousands of identical items at a dramatically lower cost per unit. It made well-designed, reliable products accessible to everyone. This is one of the foundational contributions of industrial design, and a genuine one.

But mass production has a prerequisite: products must be standardized.

In the footwear industry, this requirement is embodied in one core system — the shoe last and the sizing system.

A shoe last is the "skeleton" of a shoe: a three-dimensional model shaped to approximate the human foot. Every shoe is formed around a last — its shape determines the shoe's interior volume and, ultimately, whether the shoe actually fits. A brand's lasts are often among its most valuable technical assets, refined over years by experienced craftspeople.

The sizing system is the last's "distribution mechanism." To serve as many consumers as possible, manufacturers categorize feet by length, dividing them into discrete sizes. Starting from a master last, they scale up and down to produce lasts for each size — covering a wide range of consumers without multiplying development costs too dramatically.

The last defines a shoe's three-dimensional form; the sizing system determines how many versions of that form get made and how wide a population they're meant to cover. Together, these two tools have kept the footwear industry running for over a century. But when I began to look more closely, I found some fundamental cracks running through the system.

The Sizing System: Decades of "Good Enough"

Start with the basics: where do shoe sizes actually come from?

The underlying logic of shoe sizing is incremental scaling — taking a master size as a reference point and adjusting the pattern up or down by fixed increments to produce different sizes. It sounds rigorous. But here's the first problem: the body measurement data this system is based on was likely collected a few decades ago.

Human body proportions have changed significantly over the decades, driven by shifts in nutrition and lifestyle. The most common women's shoe size today is no longer what it was when the baseline was established — yet the reference sizes used in footwear development have been updated at a glacial pace. In other words, the entire industry is navigating with an outdated map.

The second problem: conversions between different sizing systems aren't precise. They're approximations.

European sizes, US sizes, UK sizes, Japanese sizes, Korean sizes — each is built on a different incremental logic. What does a European 36 translate to in US sizing? Depending on the brand or the reference chart you consult, the answer might differ by half a size or even a full size. This isn't because anyone made a calculation error; it's because these systems were never designed around a shared logic in the first place. The conversions have always been "close enough."

Someone did recognize this chaos and attempted a solution: Mondopoint, a global unified sizing system that uses foot length in millimeters directly as the size. In theory, it eliminates all conversion problems. In practice, it largely failed. The existing systems were too entrenched — production workflows, technical documentation, and consumer habits across the entire industry had been built around them for generations. No one was willing to pay the cost of starting over.

The third problem — and the most fundamental one — is this: shoe sizes only measure length, but length is far from the only thing that determines fit.

Feet don't scale uniformly. Going from a size 36 to a 37 increases length, but foot width, instep height, and the three-dimensional curvature of the heel don't increase at the same rate or in the same proportions across different people. Medical research also suggests that gender alone is an insufficient basis for foot classification — ethnicity and geographic background significantly influence foot morphology as well.

None of this is captured by shoe sizes. A size is just a number that tells you roughly how long your foot is. Width, height, volume — you'll rarely find that data anywhere on a shoe.

From a medical standpoint, the consequences of wearing ill-fitting shoes aren't just discomfort. The damage to bones and muscles is real and cumulative. Chronic poor fit can compromise foot health, cause lasting skeletal deformation, and affect the rest of the body in turn. Wearing shoes that actually fit is, in a quiet way, an act of caring for your own health — and the current system makes that remarkably difficult to do.

The Core Contradiction of the Footwear Industry

By this point in my research, a fundamental structural conflict had become impossible to ignore:

Using the same shoe to fit every different foot in the world is, on its face, an unreasonable proposition.

The last-and-sizing system is a reasonable tool — it balances mass production's need for standardization against the reality of human variation. But it was never the best solution. It was always a workaround. It operates on the assumption that if two people have feet of the same length, those feet are similar enough to be fitted by the same shoe. But no two feet are alike. Width, instep height, heel shape — these dimensions are entirely invisible within the sizing system.

So when you buy a shoe in your size and end up with blisters on your heel or painful pressure on your instep, it's not because you chose the wrong size. It's the predictable result of how the system was designed.

This brought me back to my original question: where does mass production break down?

Footwear gives a clear answer. Mass production excels at making standardized things well and cheaply. But shoes are shaped around one of the most individualized objects there is — the human foot. That's a fundamental tension, and the sizing system has spent decades papering over it with approximations rather than resolving it.

I don't think mass production itself is the problem. It has put well-made, affordable shoes on billions of feet — that's real and valuable. But there's clearly a significant gap between "functional enough" and "actually right for you."

Could design fill that gap?

That became the central question driving everything that followed. I started to wonder: if we can't eliminate mass production, can we find a way — within its existing framework — to bring shoes closer to each individual foot, rather than asking every foot to accommodate the shoe?

With that question in mind, I left the library and walked into a factory.