Unwinding it
Ending the service, moving the person to your own entity, or losing them — three different endings with three different owners.
Ending the service agreement
Ending the person's employment
Moving them to your own entity
The person simply resigning
YoursThe provider'sCrosses the twoNeither contract
Four matters, and no share: what any one agreement covers differs by agreement. One crosses both, and the handoff is where these arrangements fail. Three endings, and only one of them is yours to start and finish.
The Ending That Is Two Endings
Your notice to the provider and the person's employment are two different endings on two different clocks.
Transferring Them to Your Own Entity
A transfer is a termination and a new hire unless local law says otherwise, and what carries over varies.
Switching Providers
Moving a person between providers re-employs them, and the things that break are continuity and goodwill.
When the Provider Fails
Your person's employer stops trading, and your contract is with the company that is no longer there.
The Person Resigns
They resign to their employer, and you may find out second, which is a problem to solve before it happens.
Redundancy You Cannot Run
The role disappearing is your decision; the process that follows belongs to an employer that is not you.
What Buying Employment as a Service Teaches
Everything that worked ran down one leg of the triangle, and everything that failed had to cross or fell outside.