A question about design goals for DID architecture

Hi
Section 1.2 of the DID architecture document here  lists Decentralizations and
Self-Sovereignty as its first two different design goals.
Is there an identity management scheme which is decentralized but not self
sovereign OR self-sovereign but not decentralized? If not, would it be better to
merge Decentralization & Self Sovereignty into a single design goal?
Best,
Karan