Making nearly disposable clothes in short runs at high volume. Originally and still primarily an online phenomenon of quick knock-offs of "runway" designs, it is finding its way into retail outlets and can actually drive novelty (trends) separate from the normal fashion creation pipeline.

Here is a pretty good article that includes a brief history: https://www.cnn.com/style/what-is-fast-fashion-sustainable-fashion/index.html

You can't find these outlets on every street corner the way you can fast food, but pretty much every mall, department store, and supermarket will have something that comes out of the fast fashion pipeline.

In addition (my opinion), it seems to be driving a boom in clothing stores, most which seem to be speeding up their style turnover. It seems to me that the underlying model is bleeding over to other retail sectors like furniture.

Like fast food, it's more about artificially created demand than true consumer demand. More and more, I see that what's for sale is what someone wants you to buy rather than things you actively seek out.