The test cases provide important information to the client regarding the quality of their product. The approach to test case writing should be such as to facilitate the collection of this information.
Which features have been tested/ will be tested eventually?
How many user scenarios/ use cases have been executed?
How many features are stable?
Which features need more work?
Are sufficient input combinations exercised?
Does the app give out correct error messages if the user does not use it the way it was intended to be used?
Does the app respond to the various browser specific functions as it should?
Does the UI conform to the specifications?
Are the features traceable to the requirement spec? Have all of them been covered?
Are the user scenarios traceable to the use case document? Have all of them been covered?
Can these tests be used as an input to automation?
Are the tests good enough? Are they finding defects?
Is software ready to ship? Is testing enough?
What is the quality of the application?