Isolation
When you're isolating images, you can't just do it randomly. Especially if there are a lot of retouchers working for the same online store. The images should be consistent with each other, and they should also look good.

The edges of isolated objects should be smooth and consistent. No hard or jagged edges!
The background should be white (255-255-255) and bear no dust, dots or any residue.
Parts of the products should not be “eaten away” and filled with white during isolation.
It’s not appropriate to cut into the products during isolation so that they become smaller then they were.
Fur should not be blurry. It should look like fur no matter if isolated or not.
Same with feathers or any other complex edges.