Some shoes stink, others don't. What happened? Is it the material of shoes?

Smelly or not has little to do with the material of shoes, because manufacturers will not choose materials that stink when they wear them. That's not ruining their business! In fact, it is mainly chemicals such as glue selected by manufacturers in the production process. Generally, new shoes should not be worn directly. Scientifically speaking, they should be washed first, and then dried in a cool and ventilated place to let those chemicals evaporate. There is another factor. Shoes come with insoles. If it is soft foam, it will stink easily. It is recommended to change insoles frequently.