If you are not an expert of the field, then you might probably miss what really makes a successful footwear: it is in fact each and every single component that makes the whole shoe as such.
Here is where the welt comes into play. The welt is a rim sewn round the edge of a shoe upper to which the sole is attached and therefore has two important functions: first of all, it forms a strong seal between the shoe and the sole, making it tear resistant. Second but equally important, it is part of the design of the footwear making it distinctive and unique.
Therefore it should not sound weird that such a small detail, often underrated by the end buyer, is actually an essential ingredient for determining style and fashion.