Speed quality cost. Pick two.

These photographs aren't very good. Yes, hundreds or thousands of photos per day is a lot. The difference between a good picture and a really good picture might be hours more setup and post processing.

This is stereotypical Chinese manufacturing tactics being applied to modeling. Cut workers rights, cut quality, setup, safety, compensation, and time to market.

In shear numbers it's impressive but when I see how they doing it, it's a face palm moment