I sell t-shirts that I make myself, with artwork I likewise create myself.
Say I have 1,000 different shirts someone can order, so I have 1,000 products available. For each product, I have 20 different shirt colors, and five different sizes. Sizes are different prices and different weights.
Now say I have decided I want to add a new size or color. Rather than go through 1,000 products and add it one by one by one, which would take many days, is there a sort of "master set" that I can just add a new size or color to, and all 1,000 products will automatically have that new size/color added to them?
I sell other products too, sweatshirts, decals, bags, etc, that would also benefit from such a feature.