First off, the only clothing I've bought from wish is socks, which are fine, if a little smaller than most American socks, and underwear, which is sized much smaller than the stated sizes. So I wouldn't recommend buying clothing, other than socks, from this site.
Most of what I buy are cheap tchotchkes, and I have been very satisfied with the quality of most of the items, and definitely with the price. I have also ordered some, ahem, adult toys, and those have all been of very good quality. Some even came with handwritten notes. Delivery can take a while, and I have had a few items that have never been delivered. However, when I've informed their customer support, they've given me a refund.
Keep in mind that this is not a website like Amazon. This is a website where different sellers, or "shops" can sell items. The website is, I think, trying to do their best to improve their customer service. One other thing- this website is based in China, where probably 90% of our goods come from anyway. To make a blanket statement that the items they sell are "fake" or poor quality ignores the fact that almost everything we buy comes from the same place.