There are various levels of "cheap." H&M's main collection would actually be at the upper tier of so-called budget shopping. A $50 blazer is actually not that inexpensive compared to a place like Walmart or Forever 21, and the quality is generally much better. In fact I have always found H&M's career-oriented clothing to be surprisingly well made.
The Divided line is more on par with other discount retailers in my experience. I never buy anything there. It doesn't even stand up to my relatively low quality control bar. This new line, I'm guessing, will be absolute bottom of the barrel, G&G quality (does anyone remember that store?). Thin synthetic fabrics, shoddy stitching, buttons falling off, nonexistant linings. I'm sure there will be exceptions but that's what I would anticipate.
My thoughts on how they will accomplish this: I am of course not terribly business savvy, but every few weeks it seems as though they are having a sale where things get marked down to $5, $10, and $15. These are items whose quality exceeds such low prices, which just didn't happen to sell well. My guess is that they will be scrapping or at least reducing the frequency of those sales in favor of offering cheap goods right from the start. In other words, this line replaces those $34-dress-for-$5 sales using merchandise that is worth a lot less from the start. That might also mean the amount of stock or styles in the other departments gets reduced in order to limit the need for so many sales and make room for the discount line.
I could be wrong, of course. Just my amateur theory.
For the record, any time you purchase anything from a major corporate retailer, you should assume something unethical happened somewhere along the production chain. I hate the fact that this is the way it is, but there is no use in denying it or being naive.