Using readability numbers as clues, not grades
Readability and text-analysis tools can reveal patterns that are hard to notice while writing: long sentences, dense paragraphs, repeated terms, passive constructions, uneven word choice, or a reading level that does not match the intended audience. They are useful for editing help pages, articles, reports, instructions, educational material, and customer-facing copy.
A score cannot tell whether a sentence is accurate, persuasive, or appropriate for the reader. Technical terms may be necessary, and short sentences can still be confusing if the ideas are poorly ordered. Use the metrics to find places worth reviewing, then edit for meaning rather than chasing a target number.