Especially untreated natural leather, it is easy to absorb water, causing deformation, fading, mold or cracking. Even leather that has undergone waterproof treatment should try to avoid prolonged contact with water.

2. Velvet and suede:
This material has strong water absorption and is prone to leaving water stains when wet. It also tends to harden or lose its luster when dried.

3. Canvas:
Although canvas shoes are relatively durable, without waterproof treatment, the canvas is prone to deformation, mold, and difficult to clean after absorbing water.
4. Wool or felt:
These materials have strong water absorption and may deform or lose their warmth after being exposed to water, with a longer drying time.