6 Quality Defects That Are Most Frequently Found In Shoes Quality Control


Shoes are part of our daily essentials. We need them when doing our outdoor activities. Besides shoe design, the production quality is a factor that can make or break the shoes.

Defects in the shoes will bring us problems like uncozy feelings or even health issues. End-users must learn about these shoe defects to choose quality shoes. Shoe manufacturers should also know how to enhance the shoe’s quality to increase customer satisfaction.

In this article, you will find the classification of defects that explains the stages of shoe defects. Also, we will explain the defects you can find in shoes along with their solutions. With this information, you can detect shoe defects and avoid them to find the shoes to your satisfaction. Let’s get rolling!

How Do Experts Classify Quality Defects In Shoes Quality Control?

The quality control process is vital in sorting out the inferior shoes based on several levels. Let’s see how experts classify the defects.

Critical Defects

Critical defects are the most dangerous defect. These shoe defects could not even meet the basic regulations of shoes. In fact, critical defects will bring danger to your health and safety. Shoe manufacturers should reject these shoes, which are considered disqualified products.

Major Defects

Major defects are shoe defects that affect the look, durability, and marketability. With the major defects, your customers would not be satisfied with the shoes. As a result, you might get a bad reputation, low customer satisfaction, and a drop in sales.

Minor Defects

Minor defects are small quality defects that cause the shoes to have slight imperfections. Overall, the shoes will still be wearable. Usually, it would still meet your satisfaction. But, it might lead to customers’ discrepancy in quality standard expectations.

Zone 1 And Zone 2 For Defect Classifications

In Shoes Quality Control, that’s important to know where is Zone 1 and Zone 2 in shoes:

Shoes Zone 1 And Zone 2 For Defect Classifications in shoes quality controlZone 1

Zone 1 is the most essential part of the shoes. It is the most obvious around the front and sides of the shoes. For instance, the toe part of the shoe. So, any quality defects found in this zone are major defects as they impact the appearance of the shoes.

Zone 2

Zone 2 is less critical than zone 1. You most likely don’t notice the area as often as in Zone 1. Examples of Zone 2 are the heel and sole part of the shoe. If you found shoe defects in Zone 2 of the shoes, they would most likely be minor defects.

The Defects You Can Find in Shoes Production

After we classify the defects, let’s see what kind of quality defects can be found in shoes quality control of the production.

Issue 1: Excessive Wax, Oil, or Glue

Defects in Shoes Quality Control and how to qc shoesIn shoe manufacturing, various parts of the shoes are bonded with chemicals such as glue, wax, and oil. When the workers use too much of these chemicals, it will leave a residue on the shoes. This residue will then affect the appearance of the shoes and leave you unsatisfied.

This quality defect is the most common major defect you can find in zone 1 and zone 2 in shoes. Often, you can clean these adhesives easily. But if you didn’t notice and clean it before packaging, customers will be unsatisfied with its look.

Solutions to Avoid Excessive Wax, Oil, or Glue

There are many solutions to this quality defect issue. Firstly, providing training to the factory workers is the most simple solution. If they are appropriately trained, they will be able to use the correct amount of chemicals on the shoes. It will then avoid excessive wax, oil, and glue.

Also, monitoring the production line closely is a good solution. You can detect any workers who aren’t using the correct amount of chemicals quickly. It will help avoid the issue before the customers receive the shoes.

Another solution to this shoe defect is to make a quality check. It makes sure every shoe produced does not have any excess wax, oil, or glue. Even if they found it in the shoes, it will be wiped off in time before packaging.

Issue 2: Peeled Materials

You can find this shoe defect in leather shoes. It is a major defect as you can easily see the peeling on the shoes’ surface.

This issue happens because the leather or material used is of low quality or old material. It means that any scratches could easily peel the surface of the shoes. Poor equipment maintenance in production can also cause this issue in shoes.

Solutions to Avoid Peeled Materials

To solve this shoe defect, manufacturers can make quality inspections when choosing materials. That way, manufacturers can ensure the materials used are not low-quality or old. With good quality material, the shoes will not peel easily.

Also, a reminder for workers to be gentle when handling the shoes is vital. It helps to prevent careless acts and human errors when producing shoes.

Besides, shoe manufacturers should do maintenance on the equipment used. You can avoid scratches on the shoes caused by disrepair machines.

Issue 3: Weak Adhesive / Broken Stitches

Glues or stitches are sometimes needed to bond the shoe materials together. However, the glue used on the shoes might be weak. It will cause the materials to fall off and causes critical shoe defects.

Some shoes are also bonded with stitches that can fall off. The stitches are not sewn tightly or the thread used is weak.

Solutions to Avoid Weak Adhesive / Broken Stitches

There are many ways to avoid weak adhesive and broken stitches. Firstly, manufacturers can ensure a suitable adhesive is used. It will make sure the materials bond together is tight and stable.

They also have to make sure the workers use enough adhesive. That way, the adhesive can manage to bond the entire area without leaving any place out.

Manufacturers can use stronger thread for the stitches to combine the materials tightly. You’ll be able to avoid the thread being loose and the materials tearing apart in preventing quality defects.

Issue 4: Inaccurate Sizing

All shoes should be manufactured standard to the universal sizing. Customers expect the shoes they chose accurately to their feet.

But sometimes, shoes might be mislabeled or packaged in the wrong size. This shoe defect is considered critical as the customer could not even wear the shoes they bought.

Solutions to Avoid Inaccurate Sizing

You can avoid the issue of shoe sizing in several ways. Manufacturers should install the machines in the right place. That way, the shoes can be labeled correctly in the right place.

Also,  shoe manufacturers can use a packaging line to pack the shoes correctly. It can ensure that the workers know which size should be packaged onto which boxes.

Ensuring good organization in the factory can also help the production line run smoothly without mistakes. Workers can work with better focus in a clean and tidy environment to reduce errors.

Issue 5: Sharp Metal Contamination

Some shoes require nails or metal products for binding. If the nails are not pressed down properly, they could poke out. It will then hurt your feet as they pierce into your skin.

This shoe defect is hazardous as it can physically hurt the end customers. Hence, it is categorized into critical defects.

Solutions to Avoid Sharp Metal Contamination

You can easily avoid sharp metal contamination with a few solutions. The simplest way is to use a metal detector to detect the unnecessary metal objects in the shoes. Then, the workers can remove it to ensure the wearer’s safety.

Another way is that the manufacturer can set up a shoes quality control department. It can ensure that the shoes are correctly produced. For instance, making sure the nails are being pressed down properly or ensuring no metals in the shoes.

An inspection of the quality control process frequently is also a way to avoid this issue. It will further enhance your QC process to increase your brand standard.

Issue 6: Abrasion Marks

Abrasion marks are marks on zone 1 areas that are obvious to notice on the shoes. These marks are usually on leather shoes or shoes with a glossy material.

It can happen if the workers are careless or rough, leaving these marks on the surface of the shoes. Other than that, machines could also cause these marks during production.

Solutions to Avoid Abrasion Marks

Shoe manufacturers can solve abrasion marks in different ways. One of them is investigating the factors and stages of production that causes these abrasion marks. Then, the manufacturers can correct the problem in the stages to handle the shoes better.

Also, manufacturers can get third-party quality inspectors in the factories. They can check the quality of the shoes before the shoes reach the customers.

Other than that, the workers must wear proper garments. For example, the workers should avoid rings that can cause abrasion marks. They also should wear gloves to ensure the surface of the shoes is perfect, hence avoiding shoe defects.


Many quality defects can be found in shoes. These defects can be categorized into three stages of 2 zones on shoes. Fortunately, there are many solutions to mend these shoe defects accordingly. By ensuring quality checks on the shoes, you can offer your customers better quality. It will enhance your brand reputation, customer satisfaction, and company sales.

I hope this article gives you imperative information about the quality defects in shoes and their solutions. Feel free to contact us for anything about the shoes quality control.


Author: AQI Service as a professional quality control service company in China specialized in providing a complete range of quality inspection and testing certification services in China & Asia for global importers, buyers, retailers, and sellers.