White balance is an essential element of a good photo. Without it, things look too yellow or too blue, and not true-to-life, as in this example taken from Ruth Asawa's San Francisco fountain mural (toy soldiers added by some clever visitor).
You can repair some of this with editing, but paying attention to light will also help prevent the effect. As you'll see in the next slide, this image turned out far more brown and off-color than it looks in real life.
It’s also a good reminder to use this as part of a mental checklist of what to look for after taking a picture, so you don’t walk away from the scene and put all the pressure on your photo editing app. Depending on your camera app, there may be a color temperature setting you can adjust to make sure the white parts look, well, white.