Visual Stability
Confidence level: **
Status: proposed
Super-patterns
Usability Project/Pattern Language/Principle of Least Surprise
Problem statement
In the physical world, things don't appear and disappear, or sustain big changes instantaneously. Things go through gradual change which one can see. A user interface that behaves in the same way will be reassuring and calm, as opposed to one where things visually change all the time with no obvious explanation.
Displays that change abruptly cause people to lose their flow. In contrast, displays where it is clear where information came from (a window slides out of an application launcher that was activated), or went to (a just-taken photo slides into a "photos" folder icon), make things more predictable and allow people to keep their flow.
Similarly, animations should have a purpose. Pulsating elements can be distracting if they just pulse for no reason (as opposed to indicating that the element requires immediate attention). Visible flicker, visible relayouts, and things that change position instantly are distracting. Excessive use of "on mouseover" prelighting can make an interface feel brittle.
Therefore:
Instead of having something appear or disappear instantaneously, use an Animated Transition that lets people know where that thing came from or went to - thus tying that thing to Cause and Effect. Use animations sparingly and only for a purpose.