For many centuries all clothing was made of natural fibres, because there was no other available option. When synthetic materials later developed they tended to find their way into common, everyday clothing. But the advantage of the synthetic materials was almost always cost; they could either be produced cheaply or already existed as a by-product of another manufacturing process. Good quality formal wear and quality suit stayed with the classic, natural fibres. This was not a matter of being conservative; natural fibres just seem the better wearing product.
Polyester – Pure chemicals. This is wrinkle resistant, and used for a lot of clothing. It does not breathe very well, so it can get hot and sweaty. To be fair, it can be quite good when combined with wool.
Rayon – Recycled wood pulp with a lot of chemicals. This can be brightly coloured, and it can work well for embroidery; but rayon clothing wrinkles easily.
Nylon – From the oil industry. This is quite tough, but it does not absorb moisture or breathe well. Many find it rather sterile and aesthetically unappealing.
Classic Natural Fibres.
Wool. Either sheep of goat wool, this has been in use for clothing (in varies styles) for centuries. It is quite good a keeping its shape, is reasonable strong, and it manages to be warm and still breathe well. Wool is suitable for all but the most extreme temperature conditions. The material will pill under some conditions.
Cotton – Actually a plant product. This is low allergy risk and resists moths and mites. It is the best choice for hot weather as it breathes well, soaks moisture and keeps the skin dry. It is prone to wrinkling and staining. Many find is feels comfortable and looks pleasing.
Cheaper materials are like plastic, in cases like polyester and nylon this is literally so. There are many common products made from plastic, and we do not want to do away with this, but almost all fine furniture, art, and other luxury good are made from natural materials, like wool, cotton, wood or quality metal. Tailored suits follow the same pattern. Fine suits will always be based on the finer materials.