A Test Is As Good As Its Ability To Fail When It Needs To

The article warns that tests can give false positives when the tested action brings the system back to its default state.  For example, testing a modal close button can pass even if the button is removed, because jQuery silently ignores missing elements.  This happens when an action returns the component to a negative-by-default state.  Solutions include asserting the open state before closing or using a DOM API that throws on missing elements.  The key is to write tests that actually verify the functionality, not just pass.