No one has time to get things done anymore. Sure, we may have 15 minutes to spare here and there, but we feel as though we don't have enough time to accomplish any big task. That is where the word "quick" comes into play.
When writing a nonfiction ebook on how to do something, we need to take into account that most people think they can't do what they want to do. Instead of giving people a monumental goal to attain, such as losing weight, we need to create a step by step plan with small tasks that take 15 minutes or less to complete. This is why 5, 10, and even 15 workouts are so popular. Anyone can spare those few minutes each day to reach a higher goal of losing weight.
Using the word "quick" in a title tells the reader that this is something she or he can accomplish in a small amount of time. If you title your book "How to Lose Weight," readers automatically assume that this will be a long and involved process. Change your title to "How to Quickly Lose Weight" and readers will believe that the book will give them quick steps, tips, and tricks to cutting back the weight with minimum time involvement.
Take the main goal of your ebook, such as writing a romance novel, and break it down into small steps. For example, create a story summary, create a rough outline, fleshing out the outline, writing the novel, naming the book, and getting a cover made. You can go even further by breaking down the main steps into even smaller, less time consuming steps. When you are through, you will have a step-by-step how-to book that will show readers how they can write a romance novel quickly and with minimal effort.