Sizing is a variety problem

Apparently only 30% of _ consumers are able to buy shoes that exactly fit their feet and 50% say they have trouble finding clothes sizes that fit, although this varies depending on the type of clothing. If deciding what sizes to provide is the task of product planning and the purpose of size design, then a country that supplies only 50% of its consumers with the right size clothing and only 30% with the right size shoes can hardly be said to be performing satisfactorily in these fields.

This was said by Genichi Taguchi -noted lean manufacturing guru- and he was talking about Japan. As much as we complain about clothing fit and sizing here, were we forced to make a guess, I think most of us would have expected that a homogeneous society like Japan would be less likely to have consumer dissatisfaction with clothing sizes. And as it turns out, they don’t. Interesting, no?

Taguchi defines sizing as a problem of variety, not quality and the issue of sizing intervals as standardization. Now, for the individual, not being able to find a shirt in the correct size is a problem of quality but if the number of sizes were increased (varieties), manufacturers would be subdividing the market into smaller segments which causes still more problems. In other words:

Increasing the number of sizes is a question of increasing the number of varieties, but it is also a measure to counter the quality problem of the loss caused by the unavailability of exact sizes. The principal aim is to solve a quality problem through market segmentation. In summary, the variety problem is to provide a wide selection of colors, patterns and sizes to meet people’s individual needs. Deciding how much demand there will be for these colors, patterns and sizes at a given price is a product planning problem.

Should I excerpt more from this book (Introduction to Quality Engineering)? It’s kind of intense but he has some interesting things to say. Or perhaps I think it is interesting as it is self serving? I don’t see any other way to meet the demand of smaller and more specialized sizing segments than to have more manufacturers -like DEs of course- producing sizing varieties specific to under served populations.

Please refer to the other articles in this series which offer substantive supporting material. Add to the discussion rather than backtracking to topics discussed elsewhere. It is likely that the exceptions you’ve thought of have been dissected in depth. For your convenience, links open in a new window or tab.

The Myth of Vanity Sizing
Fit and Sizing Entropy
Push manufacturing; subverting the fit feedback loop
Sizing evolution
Shrinkage and fit
Alternatives in Women’s sizing
Tyranny of tiny sizes?
The history of women’s sizing pt 1
The history of women’s sizing pt 2
The history of women’s sizing pt 3
Sizing is a variety problem
The birth of size 10?
Vanity sizing shoes
Tyranny of tiny sizes pt.2
Vanity sizing: generational edition
Vanity sizing: generational edition pt.2
Vanity sizing: the consumer spending edition

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  1. moss says:

    This reminds me of a book I heard about that talked about “Long tail” marketing… Where amazon, for example, sells not very many pieces of a huge variety of things.

    here is a Wired article about it.

    here is the book.

  2. Bunny M says:

    Interesting stuff. I’m not at all surprised to learn that only 30% of Japanese people can find shoes that fit. This is because in Japan, most shoes come in Small, Medium or Large! I learned this when visiting a friend who lives in Tokyo – I bought some cute shoes, and when I showed them to her, she asked me what size they were. I turned them over and was stunned to see them marked (M)! Any time she travels out of the country she makes a point to buy shoes. (I’m guessing this also helps the sale of imported shoes there.)

    Sizing is a vexing issue for my own little company (we are less than a year old, and so small that we still make everything ourselves, though we are starting to think about outsourcing at least some of the simpler steps before long. I’ve ordered your book and am eagerly awaiting its arrival – you have great info here.)

    We currently make hats in two sizes, and some relatively simple garments in XS-XL. Right now we’re not planning to produce anything especially fitted, but that may eventually change. People keep suggesting we make our hats in kids sizes, which is a daunting idea considering how many different sizes that would surely entail.

    I love your site, and am eagerly soaking up all the info I can. It’s very inspiring and I appreciate all the info you are putting out here. Thanks!

  3. Eddie says:

    I’m not at all surprised, either. Here in Japan, a lot of the stylish boutiques (called “select shops”) carry only “Free Size” clothing, which is a one size fits all. The customer is expected to accept that the genius of the designer comes in only one size and make do with what’s available. Others carry the equivalent of S, M, and L.

    I think this generally works in Japan because, of course, people are more homogeneously sized, but also because the oversized, layered Mary Kate and Ashley Olsen boho homeless look continues to be popular. And people are more concerned with the cachet of a particular brand and its look rather than the actual fit. If you look closely at the men and women on the subway in Tokyo, you will see a lot of ill-fitting or just plain baggy clothes– European suits and American-cut shirts that aren’t quite filled out, paper bagged waists, too long jackets and skirts, etc.

    I’m a small-boned American and am often embarrassed to find that I’m too petite to find stylish Japanese clothes in the fit I like. (I prefer classically tailored clothing.) Or, when my “size” is available, my healthy American-sized behind strains the seams. So sadly, only Japanese knits for me and the rest is all foreign brands…

    What I was trying to say is that the Japanese might be more forgiving about the limits of up and coming designers, so you all should sell there. :)

  4. Sonia Levesque says:

    I find this subject utterly important and interesting.

    As a DE specialized in Plus Sizes fashion for women, you can just imagine I think about the sizing and fitting issues daily. Only “made to measure” clothes can really respect one’s body, even more so when we understand that nobody puts on weight quite the same way… I can charge A LOT for my made to measure services. But find it so tiring to do on the long run.

    So I’m starting to think “ready to wear” again. And puzzle right now at the design answers (and grading too!) that will cater to most… And in the end I come with only one answer; I can only satisfy so many women. I must choose a silhouette and style proportion and stick to it.

    Frustrating scenario. Learning life experience, I tell you, letting go of your “let’s please EVERYONE” need.

  5. Jessica says:

    When I was living in Japan I noticed that many adults wore ill-fitting shoes. It was not unusual to see a man or woman whose heel was hanging off the back of an undersized shoe. About the largest woman’s shoe sold in Japan would the equivalent of a size 7 in the US. As a tall woman, I didn’t even bother with shoe shopping. I was given a few pairs of shoes while I lived there. These were one-size-fits-all shoes designed to be worn with summer kimono, but they were far too tiny for my foot. Japan seems to expect homogeny in sizing, and even the newer architecture is not really built with contemporary heights in mind. Contrary to stereotype, there are some tall men and women in Japan. I knew some men that fell into the 6’3″ range, for example. However, my apartment had doorways that couldn’t accommodate a six-foot-tall person unless he stooped, and the building was newer construction.

  6. berry berg says:

    I would like to know if there are any industry published materials pertaing to allowance for elastic sizing for women’s leggings.

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