Large images are visually appealing, but they can harm the overall user experience if they aren’t appropriately prioritized.

Source: www.nngroup.com

The entire Southwest homepage is designed to focus attention on the image: the top navigation links are small and have no background color; the search function is represented with a magnifying glass icon instead of an input box, and even the Book now call to action button is an understated outline, with no background color to distinguish it from the background. Most importantly, the flight search function is pushed several inches down, so that it doesn’t interrupt the image. As a result, many users won’t even see the button to search for flights until they scroll down the page.