Interview frequency: …
Short answer
Also called the Isolation Effect, it says that when several elements are similar, the one that looks different from the rest is more likely to be remembered and attract attention.
Explanation
Pricing tables often use this principle by making the "Most Popular" plan larger, giving it a distinctive color, and adding a special badge to make it stand out. Dialogs use it to make the positive action button prominent and filled with a distinctive color, while making Cancel subtle or a simple text link.
Common mistakes
- Highlighting more than one element at a time, creating visual conflict and eliminating the isolation effect.
- Using a loud highlight color on an unwanted secondary element, distracting users from the primary goal.