It can be said that the goal of testing is simply to describe what you have done. By describing, you are forced to assert your assumed truths about how something operates. When these assertions are executed, we can then discern whether our descriptions, our assumed truths, correctly reflect reality.
In the act of description, we must choose our words carefully so that they express our meaning clearly and comprehensibly. Tests are one of our last defenses against obscurity and complexity. Some code is unavoidably complicated, and we should ideally craft it in a way that reduces its obscure nature, but if we can't fully do this, then it is the role of tests to clear up any remaining confusion and provide the final point of clarity.
The key to clarity while testing is to focus purely on the perspective of the person who must read through the tests ...
