What are the qualities that a good Agile tester must possess?

The good qualities of a tester are as follow:

1. An agile tester should have a better and quick understanding of the requirements.
2. Agile principals and concepts should be known by the Agile Tester.
3. He should be able to understand the risk involved in the requirements as they always keep changing.
4. Agile tester, based on the requirements, should know how to prioritize the work involved.
5. An agile tester must be able to communicate with the business associates and developers as their work depends upon better communication.