I worked a good number of years doing tech in fashion.

Figure that there is a 100-1000% markup for a garment at retail. The jeans that cost $3 to make versus the ones that cost $13 will sometimes be durable, but you are basically buying the quality of the seamstress beyond materials at the higher price point.

But compared to other types of clothes I find that they last a long time. I buy a new pair every year from Nudie Jeans for $140 and they last around four years (with the included free repairs). And when they are worn out you get 20% discount on new ones if you hand in your old pair.

The prices rise to fit the market. People will pay for the "fashion" and brand name so the retailers sell them. You also have layers of outlets, overstock, discount retailers, thrift stores and more that take up the overflow. a

I guess it depends. I buy levis which are the some of the cheapest decently quality jeans you can find. I'm not big on raw or selvedge denim so I mean decently trendy and ready to wear jeans. I can find a pair for around 100 or less depending on sales and those pairs can last me about 3-5 years. I think 100$ is a fair price for something that will last me that long. I have squatter's legs so the inner thigh grinds to a pulp on most brands but levi's lasts the longest.

Yeah, You can get some OK ones between 30-50 but the more stylish ones are easily >100 or way more.