Self-custody means the private keys controlling your funds are held by you, not a platform. Whoever holds the keys owns the asset in practice — everything else is an IOU.
Specter wallets are self-custodied: Specter never holds user private keys and cannot freeze anyone's money. That is a structural guarantee, not a policy promise.
The custodial trade
Custodial platforms offer convenience priced in control: they can halt withdrawals, close accounts, and lend against deposits. Self-custody returns the default: your keys, your call.