Ignite/Death Mark, your target still has 3 or 4 seconds of doing nothing, while you can just pour out damage on someone else. Kayle, Zhonya's, and Kindred prevent you from killing them out right, which is downright annoying, especially when you know that death mark will kill them. Kench can be dealt with pretty handily, and shadow swapping should prevent nomming. Where Kayle, and Kindred can just go and deal damage possibly leading you your death when the ult is up. Especially with the heal on the Kindred ult