How Often a Wallpaper Should Change
A picture you have stopped seeing is not doing much work.
Somewhere around the third day, a wallpaper stops being an image and becomes the color of the desk. The eye files it under furniture and moves on to the icons. Nothing is wrong with the picture; it has simply been looked at enough times to become invisible, which is the fate of anything that never moves.
Most slideshow settings offer to fix this with a change every minute, or every ten, which trades one problem for a worse one: motion where you wanted a background. Once a day, or once a week, sits closer to the truth. So does keeping the rotation small. A folder of five hundred images gives you strangers every morning; a set of eight gives you something you recognize, and recognition is what makes a change register at all.
It helps to choose pictures that survive being ignored. A horizon, a field of a single color, water doing almost nothing — these hold up under a hundred glances, and they still have something left on the day you actually look. The best wallpaper is one you notice twice a week and forget for the rest of it.
