A Small Difference That is Effective

User animation teacher and prophet Edward Tufte is known for saying that when the UX designer wants to call attention to something on the interface, the smallest effective difference — that is, the smallest possible change — that the user will see is the only one you need.

This is known in UX as an ‘indicator’ — something that tells the user what they can or can’t do on the screen, or something that indicates how or where they can find more information about some subset of what they are looking at.

We think about difference often because it defines who we are, what we want, what we desire is contoured by the boundary of what we are and what we are not. Too often our instincts are to accentuate the difference but this typically confuses the user as it creates an anxiety experience.

In a digitally native world your successful enterprise will understand and capture on the information wave that is intuitive interactive design. 

The subtlty should not be understated: too much difference creates cognative confusion for the user. Humans subconsciously strive for internal consistency. Experiencing inconsistency leads to psychological discomfort. Thus, when things are aligned we experience happiness. 

There are three basic ways we deal with cognative dissonance: 

1. Ignore/deny it
2. Justfy the dissonance by rationalization
3. Change something

On a user interface, it’s hard to ignore/deny a large cognative or display problem. Typically users will attempt to understand the conflict by understanding the intentions of the application (#2), or they will attempt to change something by clicking around (#3).

The smallest possible difference or slightest effective difference means the smallest amount we can change that will get signal the meaning for the difference to the user. 

Sometimes a smallest change can make all the difference for your visitor’s experience of your application.