Three times while building a web content extractor, a passing check told me something that wasn't true. Not a flaky test, not a missed edge case — a green result that actively asserted the opposite of reality. All three failed the same way, and once I saw the pattern I couldn't unsee it. The three The benchmark said 90% of pages extracted successfully. The success test asked whether the extractor returned at least 200 characters . A section landing page — a site homepage,...