These days when folks need a belt they usually get a factory-pressed piece of cloth or split leather (suede) with a bit of plastic/vinyl stamped on it. This artificial leather (usually called "genuine leather" in a bit of ingenious branding) allows leather products to be mass produced but they don't have the long-lasting durability of natural leather. Any belt from a big box store is going to fall into that category and for me they usually last 1-2 years and then I need to replace them.
To compare that with a full-grain, natural leather belt I inherited a small belt from my father when I was about 9. He'd gotten the belt as a kid from his father who'd worn it back when he was a kid. Doing the math I can guess that this belt was made somewhere in the 1920s-30s (before artificial leather was developed during WWII) and when I received it in the 90s it was just fine. I wore that belt every day until 2003-2004 when it finally snapped. I'm sad to say that if I'd been conditioning it properly all that time (and not folding it to stuff it in my boots at night) it'd probably still be around (whether or not it would fit would be another matter).
A couple of years ago, back when I had a better opinion of Tandy, it was time for me to replace the belt I was wearing at the time. Tandy has a pre-built belt they sell at a price point that certainly implies that it's full-grain leather. The exact price up here fluctuates with the exchange rate but it's about triple what I'd pay for a similar belt at a retail store. I figured that was probably a bargain if it meant I wouldn't have to buy another belt for at least a few decades. Well it's two years later and that belt is in worse shape than the belt that preceded it.
Tandy's belt is built on a heavy split leather, a bit under 1/4" thick, but they slapped a cheap vinyl on top that. The vinyl's wearing away and wrinkling as the leather molds over time to fit my waist. The construction is solid enough but as a leatherworker the finishing is nothing short of shameful. Fortunately, I could do something about it.
Belts aren't that complicated to make compared to most of my other products. You take a strap of heavy, quality leather, in this case 9 oz Italian veg-tan, and you shape it by punching holes, beveling, burnishing, etc.