How to Address Quality Control Defects in Shoes

Every product produced has a life cycle, and shoes are no exception. Even well-made shoes will eventually wear out over time. But that doesn’t mean clients are responsible for any wearing defect or other defects.

Although shoes are made of sturdy and reliable materials like plastic, leather, and rubber, they are also prone to have defects. Therefore, it requires that the shoe factory control the problems in the production of shoes, and then they minimize or eliminate the common faults that occur in shoes. 

By doing that, you can make your clients feel satisfied to get a steady stream of orders.

Whether you are an importer of high-quality shoes from a factory or a consumer who picks up high-quality shoes from a retail store, it is helpful for you to know these common shoe defects.

In this article, we’ll look at the six most common quality control defects in the shoe as manufactured and how to address them as much as possible.



Nike running shoe manufacturer
The picture is from Nike’s Official Website

1.Definition of Shoe Quality Defects

First of all, we have to understand the concept of shoe quality defects, and only we know where the defects are can we take the proper measures to solve them.

So, what is the definition of shoe quality defects?

Nike running shoe manufacturer

(The picture is from Nike’s Official Website.)

The following conditions of shoes belong to the quality defects: different size, broken upper, broken bottom, leather surface off, serious desizing, glue, open thread, and heel drop, according to the “National Guarantees Law of Repair, Replacement and Return of Footwear Products and Service Details” and the “Consumer Rights and Interests Protection Law of Footwear Rules.”

There are not in the scope of shoe control quality: odor, color difference, accessories easy to fall off, unidentified glue stains, scratches that cannot be clearly distinguished by naked eyes beyond 1.5 meters, or minor defects not affect the wearing. The error within 1 cm is not a shoe quality problem.

2. How to Inspect Shoe Quality? Is the Shoe Factory in China Dependable on Your Shoe Business?

Nike running shoe manufacturer
The picture is from Nike’s Official Website

Before testing shoes, you need to know the three categories of shoe quality: “A,” “B,” and “C.” Here are the detailed descriptions.

A Grade

A Grade shoes are high-quality shoes without any defects in appearance or functionality. They are made to the highest quality standards, so they are more expensive. A Grade must meet product specifications and match with the approved confirmation samples.

B Grade

B Grade shoes are those that do not have any significant functional defects but may have appearance defects, manufacturing errors, or artistry problems that cannot be adequately repaired. B Grade shoes will be discounted or sent to markets that are more tolerant of such defects.

C Grade

C Grade shoes may have significant defects in appearance and functionality, which cannot be repaired. Such shoes should not be sold because they are poorly made and harmful to the wearer and make the brand or company’s reputation at stake. In short, C Grade shoes should be destroyed.

After knowing the quality grade of shoes, want to know how to check the quality of shoes?

Here’s a guide to identifying shoe quality control defects.

Check whether the top and bottom of the shoes fit perfectly, whether there is opening glue and whether there are holes.

Check whether the back seam is smooth, whether there is concave and convex, whether the toe is round and smooth.

Check whether the collar is smooth and good-looking and whether the three points of the toe, the midpoint of the collar, and the back seam are in a line.

 Check the length of a pair of high heel shoes. And the method is to align with the two heels and then tilt up to check whether the toe is flush;

 Check whether the cony of the outsole is the same width and whether some places out, more or less, to see whether the stuck outsole is crooked.

 After checking the upper, then check the lining. It’s easy to see if the waist is bulging, if it’s wrinkled, if the footpads are stuck askew, if it’s tight, and if it’s fitted.

Finally, check the cleanliness and see if there is glue on the upper, lining, and heel.

As for the shoe market, the shoe-making industry is highly concentrated in Asia, which accounts for about 90% of the world’s total production of shoes. Almost nine out of every ten pairs of shoes are made in Asia.

In 2019, 24.3 billion pairs of shoes were manufactured globally, of which 13.475 billion pairs of shoes were produced in China. With a global share of 55.5%, China ranked first among the world’s top 10 footwear producers, much higher than other countries. India is next at 10.7%. It is followed by Vietnam (5.8%) and Indonesia (5.1 %).

The footwear output of these four countries accounts for more than 75% of the total global production. That is enough to prove that the Asia-Pacific region (including China, India, Vietnam, and Indonesia) is the leader in the footwear industry.

If you are looking for private label manufacturers or shoe s factories in China, please contact us by email:

We are a leading shoe factory or private label manufacturer located in Jinjiang city, “the shoe capital of China.”

The minimum order quantity provided by our shoe factory is 1000 pairs of leather shoes and 1500 pairs of sports shoes. You can contact us for details. We have a range of high-quality A-grade shoes, and all exported shoes have been passed by third-party quality inspection.

3. Pay Attention to 6 Common Quality Control Defects in Shoes as Manufactured or Bought

Shoes Quality

Whether you’re importing shoes from the shoe factory in China, Indonesia, India, or Vietnam, you need to pay special attention to functional defects as well as cosmetic defects. Moreover, functional defects are not acceptable.

Usually, with the shoe factory in China, you don’t have to much worry about shoe quality control. There are thousands of shoe factories in Jinjiang city, China, and leading shoe companies such as Nike have confidence in the country’s shoe industry.

Let’s take a look at the six common shoe quality control problems that every factory owner must identify and address.

3.1 Over Cementing

Shoes glue quality

Each part of the shoe is usually sewn and glued together. If the glue is applied unevenly or excessively, too much glue will seep out of the edge of the sole. In general, as for the glue line, it is normally considered that the glue line below 1mm is acceptable. If the glue line is more than 1mm, the shoes will be sold at a discount.

However, do not worry a lot! These glue marks can be easily wiped off during manufacturing; however, if the glue marks may look ugly, which will affect the client’s purchase or make the client ask for a refund.

This shoe quality control defect is that the orders are too urgent, and the workers do not deal with it in time when they apply it too much. That requires training shoe factory workers to use enough glue; If the bond comes out, erase it. Of course, it can also be fixed in the subsequent steps of the production process. You can save a lot of money by solving this problem.

3.2 Gaps or Weak Glue

Gaps Or Weak Glue

Weak glue is also a common defect of shoe quality control. Generally, for example, rubber soles of sports shoes, weak cementation will occur when the amount of glue of rubber sole is insufficient or wrong. Or, if the shoe factory doesn’t use the correct type of adhesive or low-quality adhesive, its shoes will be found to have this common defect.

That condition is likely to crack after a short period of use, which will prompt your client to return the shoes.

As a person in charge of the shoe factory, you have to check whether the workers use high-quality glue in shoes and use enough glue.

3.3 Asymmetry


Asymmetry is another common defect of shoe quality control, which is a very prominent appearance defect. The asymmetry in shoes is usually related to the cutting or fitting of parts. Some parts of the shoe may be asymmetrical. One shoe may be higher than the other.

The best way to check for asymmetry in shoes is to place a pair of shoes side-by-side or back to back. It would be best to make sure the shoes are the same in height, width, and color. In addition, check the soles for discoloration. No matter which part is asymmetric, it may lead to a client’s refund.

In case of asymmetry, the clients must contact the shoe factory or manufacturer to determine the problem and demand that the defect is resolved.

3.4 Wrinkles or Puckering or Creases or Waves

Wrinkles Or Puckering Or Creases Or Waves

The sole of shoes is easy to wrinkle in the production process, which is a fatal defect for shoes. Once the wrinkled shoes flow out, it will cause considerable losses to you, and clients will ask you for a refund and compensation. In general, after high-temperature treatment, the soles of shoes will be prone to shrinkage and wrinkle. After the shoes are pressed, the soles will also appear wrinkle, especially when the pressure of the press is set too high, the sole of the shoes and the sole mold in the press do not match, and the sole mold is damaged.

The paint on the outsole will be more noticeable. Usually, after the press to use, the outsole wrinkle machine can effectively reduce or eliminate wrinkles. Generally, after using the press, it can be effective to reduce and eliminate wrinkles by the machine of wrinkle remover.

Sole material

Of course, in addition to the outsole, some of the wrinkles are on the upper, and there are two main reasons for this wrinkling. The one is the layout of upper. The layout of upper is too large, the last is not suitable, and the arc of the instep is not enough, which makes shoes wrinkled easily. The other one is the workmanship. The instep of the vamp is not shaped or the arc of instep is not caught. The upper needs to be shaped after stitched, if not, the upper is loose. The cooling time of sulfur addition is insufficient, and the material is delamination, which is very easy to make shoes wrinkle. To solve the wrinkles of uppers, it requires the shoe factory to adjust the layout or workmanship of shoes according to the specific causes of wrinkles.

3.5 Dents

Upper Dents

Dents are the marks on the vamp, especially in leather shoes. If it is not handled carefully on the upper, dents will become apparent immediately. This is due to the improper handling and packaging of shoes in the production process.

Once you find the defect in shoes, you will need to investigate which stage of the production process has the defect and deal with it accordingly.

You can check to see if shoes are moved unnecessarily between workers and handled rudely for bulk orders. Most importantly, make your packaging smooth enough to prevent any dent.

3.6 Wrong Sizes

It does not mean that the shoes are the wrong size. Due to an error in the production process, the shoes were labeled and packaged in the wrong size.

Although there is no apparent defect, it should be considered a significant defect in selling because shoes that do not meet the size specifications are likely to be unsaleable. 

In good footwear production, it is not common the size of shoes is inconsistent due to the manufacturing arts. The wrong size is usually caused by incorrect classification and packaging of finished shoes. As a result, shoe size errors are more common in disorganized factories.

To prevent the wrong sizes, it is necessary to ensure that your staff handles, packs, and stores shoes in an organized way. Check the shoe factory’s warehouse and parking area to see the various possibilities for incorrect sizing.

4. How to Come to Stop Quality Control Defects in Shoes?

Nike basketball shoes factory
The picture is from Nike’s Official Website.

After knowing the common defects of shoe quality control, we need to know how to stop the frequent occurrence of these issues, which requires the shoe factory to carry out a variety of quality tests.

That requires the shoe factory to have quality inspectors check the six quality control problems for each shoe and cooperate with the third-party inspection agency that is satisfied with clients.

The shoe factory can invite a third party quality inspection agency to conduct a fair review, which will perform the following tests:

• Cartons assortment check (if applicable)

• Sampling Size Test               

• Carton Drop Test  

• Match packing Info                • Zipper test    

• Shaken Test Info                  • Pull test

• Mold prevention check             • Fatigue test   

• Rubber curing check               • Odor check

• Rubbing (textile) test               • Adhesive test  

• Waterproof test (Footwear)         • Wobbling test

• Color shading check                • Bending test

• Sole Binding Check              

• Bend or Flex Check

• Color specification check

• Broken needles record check

• Metal/needle detection check 

• Material strength check (Footwear)

• Symmetry check (Footwear)

• Seat piece attachment check (Footwear)

• Lace-up check (Footwear with laces)

• Quantity and assortment check (per package)

• Barcode scanning test       

• Approval sample comparison

• Stitch density check           

• Wear test (Footwear)

5. Where to Find Shoe Factory?

Private label shoe factory production workshop

If you want to know where to find reliable private label manufacturers or shoe factories that provide shoe quality control, China is the right choice for you. (Related article: How To Find Reliable Shoes Suppliers In China ? )

Although the epidemic has occurred again in some parts of China, it has little impact on China’s economy. With the strong policies of the Chinese government and the self-discipline of the Chinese people, China should be one of the safest major countries globally, and it is developing steadily in all aspects.

Provide more choices to choose shoe factories in China. China shoe factories are the best choice because of the cost of raw materials, packing charge, quality of shoes, delivery time, payment time, factory environment and response speed, after-sales service, and other factors.

China has the advantage of mid-end labor costs. Although China has not a very cheap labor market, the quality of its workers has improved dramatically, and the mid and high-end labor force has an apparent advantage.

China is the only country in the world that owns the whole industrial chain and has the qualification to compete for the commanding heights of the next generation of new technologies. 

Therefore, where to find a shoe factory? It must be in China. More shoe factories, more choices.


Test qualified orange running shoes

XIN DE SHENG SHOE FACTORY is a leading private label shoe manufacturer or a top shoe factory in China, which has passed the ISO 9001 Quality Management System Certification. Our shoe factory is located in Jinjiang City–“the shoe capital of China,” which is very convenient. We have an export department responsible for international orders of shoes. 

Our shoe factory mainly provides private label running shoes, private label sneaker shoes, private label casual shoes, and private label hiking shoes. Our main clients are primarily from the United States, EU countries, such as Tommy Hilfiger, MMK, Le Coq Sportif, Wenger, Japan FILA, LA-GEAR, VICTOR, 4F, and other private label designer brands.

We At China Shoe Factory perform a number of quality checks to prevent such common defects. When you place orders with us, basically, you will not find excess glue, weak glue, wrinkles, dents, asymmetries and wrong sizes, and other shoe quality control problems. Although the shoe factory in China has thousands of orders to handle, we have a large number of workers who pay Attention to detail and quality.

Test qualified red white running shoes

We are well aware of the compliance and quality requirements of the United States and the European Union. We can meet even the most stringent testing requirements of Germany and Turkey! Our shoe factory has been producing Japanese FILA shoes for a long time, so shoes’ quality can be guaranteed. There is less worried about the quality of the shoes than other shoe factories.

Even minor shoe defects can cause discomfort to the user, so shoe quality control and inspection are crucial for shoe production. To ensure that the best quality standards are met, and all legal requirements are complied with, our factory strictly controls the quality of shoes. We have three full inspectors on the production line, and every pair of shoes will be inspected. Before shipment, they will be checked by a third-party shoe quality control agency. So, our shoe factory attaches great importance to the quality control of shoes. Our shoe factory has been committed to providing customers with the best quality shoes.

Professional shoe factory quality testing equipment

Due to the large scale of our shoe factory, the cost of management and maintenance is relatively high, so there are some requirements for the minimum order quantity. The minimum order quantity of our private label shoe factory is 1000 pairs of leather shoes and 1500 pairs of sports shoes. 

The specific quantity can be discussed with us in detail. If you are interested in private label shoes, you can contact us via email at, and we will reply to you in time as soon as we receive it.


Detect qualified running shoes
The picture is from Nike’s Official Website

In any case, most shoes are manufactured with specific quality requirements. In addition to practicality and comfort, the beautiful and fashionable appearance of shoes is also critical. We should not only pay Attention to the function of shoes but also the beauty of shoes. Therefore, whether shoe manufacturers or customers, it is indispensable to identify and fix some common quality defects of shoes.

In this article, we introduce to you six common defects of shoe quality control that occur during manufacturing shoes and some methods you can take to solve them.

If you have any questions about shoe quality control defects, you can leave us messages. Thank you!

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