When I got interested in menswear and dressing presentably one of the important aspects of dressing well that needed serious attention was my footwear; this was about five years ago. Back then I suffered from this 'clothes for a special occasion' syndrome. I only wore certain items of clothing on special occasions or days. You would never catch me wearing a double cuff shirt during the week, it was reserved for a particular occasion or Sunday. Then, when I started learning about dressing well, my thinking changed and I embraced the idea of wearing all my clothes, all the time, no matter the day of the week. I also decided to upgrade the styles of footwear that I needed. I came across a tan captoe blucher, a burgundy captoe oxford, and a black wingtip blucher with a sharp toe. I thought I was on to a pretty good start because I was going to rotate my footwear and that they would last a long time. I use the word 'long' very loosely because I didn't bet on the fact that after five years these three pairs would start falling apart. And this deterioration is taking place at the most critical part of the shoes, the sole.
I'm not a cobbler but I surmise that my shoes cannot be repaired because glue can only hold so long until it starts wearing off, leading to a state of disrepair. See how they are all falling apart at critical parts of the shoes? The heel, sole, and the outsole. The inclusion, efficacy and strength of a welt (a strip of leather which is sewn around the bottom of a shoe) is obviated if it is glued as opposed to stitched on to the shoe.
Welt stitching is not found in mass produced shoes. You will find it with good quality shoes produced by venerable shoe companies that have knowledge and a history in the shoe making process. The the styles of shoe construction, and what it takes to construct a shoe that lasts for decades is where welt stitching is critically important.