What does that even mean?
You've been stating that if someone builds a character you don't like you'll ensure that they get killed off. That rather than talk to the player and work out a compromise you'll just make an example out of any PC built in a way not to your liking by guaranteeing that they die.
No one is saying you shouldn't set up appropriate (even quite possibly deadly) challenges for PCs. But there's a line between "these particular monster target strength/dexterity/constitution/intelligence/wisdom/charisma saves which some party members are poor at" and "I will set up a no-win encounter for PC X because I don't like that PC".