In 2019, the size of the average mobile webpage is 1.6 MB. Images usually account for about half of the average webpage because they’re so resource-intensive to serve up. If you’ve never taken image optimization seriously and your WordPress site is slow, then you have the most to gain by doing it right. If your WordPress images are loading slowly, that usually means there is a problem. By focusing on your images, you can prevent a lot of issues related to site performance.