Speed, speed, speed. It is one of the most important factors if you want good google rankings and to delight your website visitors.
If you want an easy win, you can implement one of these image optimization tools.
Most of us upload images to WordPress without taking the extra time to optimize them.
I know I don't!
This is why I rely on an image optimization plugin to keep my images lean and optimized, which makes my website load a lot faster.