Escalation is a very tough negotiating tactic. An agreement is reached between two people who have the apparent authority to make the deal. Then, one says that they need to show the agreement to someone else for "routine" approval. That's when the first surprise occurs. The higher authority rejects the agreement unless further concessions are made. A renegotiation granting these concessions then follows to settle the almost closed deal. This can go on with multiple levels, where each level of authority demands and wins further concessions to reach final agreement. Each renegotiation "tests" the resolve and the limits of the other party.