Let me try to understand:
So hardcoded checkpoints are made by the protocol?
It isnt wrote by a dev and shared with the public through a update of the protocol?
Hard Coded checkpoints are written directly into the program code of a wallet.
And only updated at the time a new wallet is created.
But they only work if over a certain % of active users update their wallet.
Checkpoints sent our across then network are usually a by a Checkpoint Server, which runs continuously.
(Checkpoint servers are a target, as controlling it means you can control the entire coin network.) 