I only ever hear about Shein in a negative light. It's never been entirely clear to me why Forever21's and H&M's disposable clothing is somehow morally superior to Shein's.
They are remarkably less disposable. That's how bad Shein is. I worked in the industry in a past life and I've seen how the sausage is made. Shein has got the nastiest sausage.
Anecdotally, I have heard that there is three towns where a predominant amount of Shein clothes are made and while people are free to leave, they’re paid in “company bucks” akin to company towns in the late 1800s/early 1900s US.
They steal designs from independent fashion designers (because designing their own clothes would cost too much I guess). It's also the volume with Shein. They produce so much crap at such low prices and it's all just dumped into an already struggling environment. Shein is far from the only one, but it's the most obvious and well known example.
I think people just look at the price and assume it must be terrible, somehow.
Fast fashion gets a bad rap because of the assumptions about consumer behavior and labor. Almost all clothing is terrible for the environment and for the people manufacturing it, anyway. I have many H&M items that are nearly a decade old and are still wearable.
As long as the piece is durable, it should be fine.
I might be extreme, as I prefer fewer stuff of better quality, that last years. Like a pair of jeans that I can wear every day for years.
I still have a few things from F21 and H&M that I bought 7-10 years ago. Definitely the exception and not the rule, but I don't think any Shein clothing can last even a fraction as long as that.