Ease of implementation. And writing test case to write/deploy bug free code. Ease to debug.

1. Very easy to use. 2. Very less configuration is needed. 3. Provide both annotation as well as class based configuration. 4. I can fully mock an object as well as partially mock an object that is very helpful when I just need to test some methods of a class which I created and leave the other methods which I do not case about. 5. Method name are fluent based so Its very descriptive for others when they read the test cases.

It is easy to use and it also provides some annotations for reducing boilerplate code.