What the price actually follows
Short answer: The price of a t-shirt follows the amount of fabric, the sewing time and how many links there are between the factory and you. Quality only partly follows along.
The three things that cost
More fabric and a denser knit cost more yarn. More seams and more details cost more minutes at the machine. And every intermediary adds its own percentage on top.
Where price and quality do track
Up to a certain level there is a clear connection. Very cheap clothing really is thinner and sewn faster. You can both see and feel it. See bamboo t-shirts for men.
Where they part company
At the expensive end you often pay for the name, the shop and the marketing. The fabric can be the same as in a garment at half the price. See bamboo clothing for women and sale.
Frequently asked questions
How do you find the good level
Judge the fabric in your hand and ignore the price until you have done so.
Are expensive clothes more durable
Not automatically. Sewing and fabric decide it, not the price tag.
Can sale items be genuine quality
Yes. A sale is usually about season and stock, not about the product.