I think it's supposed to be to incorporate air. I only sift flour if I'm making scones, it seems to make a difference. I'm not a cakey person, I don't bake cak

I think it's supposed to be to incorporate air. I only sift flour if I'm making scones, it seems to make a difference. I'm not a cakey person, I don't bake cakes. It's cake bakers that tend to care about sifting.