Should QA test from a strictly black-box perspective?

Question

Assuming that unit tests are handled by development, is there any reason for QA to have knowledge of the details of how a product works? By which I mean, do they need to kn

Answer 1

It depends on the approach and the kind of software you are writing. There are different kinds of QA. If the software should be fault-tolerant, QA should simulate faults. Also, knowing how a product works can help QA think of potentially problematic cases and test them more thoroughly.

On the other hand, knowing how a product works might prevent the QA from testing completely from the user's point of view. So maybe first the basic tests should be designed without knowing the internals, and then more in-depth tests based on potential problems.