Because what you wrote broadens the type. `satisfies` validates the type without broadening it. const c: string = 'c'; This will be of type string instead of

Because what you wrote broadens the type. `satisfies` validates the type without broadening it. const c: string = 'c'; This will be of type string instead of type 'c'. This is a barebones example and it already breaks support for template literal types. Imagine how much better `satisfies` is for complex union types.