Shadow Isles

When i was reading Kindred's quotes i noticed that when u will buy Blade of the Ruined King, Lamb will say: "Forged in a land unwelcome to us." I think i dont understand, i mean they are personification of Death, so shouldn't they come from Shadow Isles or Shadow Isles is more like place when death does not work as it should be and that's why it's unwelcome to Kindred? Sorry for my English and thanks for reading and answers.