Let’s consider three scenarios.
1. A tort. A hurts B accidentally or due to mild negligence. B has been made worse off, but A did not benefit at all from the damage to B. In fact, A may be genuinely distraught that he harmed B. In such a case we have restitution alone with no punishment attached to it. If a judge rules that B must make A whole or “restore” him, then B is thereby harmed which may very well be sufficient punishment and therefore deterrent.
2. A property crime. A steals a TV from B. B is made worse off; A is made better off. If B is caught, etc., and a restitution is ordered, then A and B return to their previous positions. B returns the TV and otherwise is not harmed by the restitution. Clearly, the deterrence stimulus is insufficient: if B is not caught, then he becomes better off; and if he is caught, then a status quo is maintained: B is no worse off than before the crime.
Therefore, an extra punishment beyond restitution is legislated for B so that theft can be deterred.
(There are of course other reasons for punishment.)
3. A murder. A kills B. Since B is dead, there can be no restitution: B cannot be resurrected. At the most, A can be forced to pay for B’s funeral expenses.
This is a case of punishment alone with no restitution being ordered.