Should black box or white box testing be the emphasis for testers?

Question

Which type of testing would you say should be the emphasis (for testers/QAs), and why?

A quick set of definitions from wikipedia:

Black box testing

Answer 1

• *Black box testing: Is the test at system level to check the functionality of the system, to ensure that the system performs all the functions that it was designed for, Its mainly to uncover defects found at the user point. Its better to hire a professional tester to black box your system, 'coz the developer usually tests with a perspective that the codes he had written is good and meets the functional requirements of the clients so he could miss out a lot of things (I don't mean to offend anybody)
• Whitebox is the first test that is done in the SDLC.This is to uncover bugs like runtime errors and compilation errrors It can be done either by testers or by Developer himself, But I think its always better that the person who wrote the code tests it.He understands them more than another person.*