Copyblogger

“Starting off your chapter title with “why” at the beginning of a declarative statement (instead of a question) is one easy way to focus in on the benefit of reading your article. That’s one of the reasons why the title of this post works, but the words that follow the “why” are what’s most important. You can do the same by starting with “here’s why,” “what,” “when,” or “how,” or you can simply make a strong statement that clearly demonstrates that the elaborated answer will be provided in the body content.”
― Copyblogger Media, How to Write Magnetic Headlines: The Fundamental Guide to the Most Important Copywriting Skill on the Planet