Design is Communication
Every visual decision communicates something to the user. Color, spacing, typography — these aren't aesthetic choices, they're functional ones that directly impact usability and conversion.
Hick's Law
The more choices you present, the longer it takes to decide. Great UI design reduces cognitive load by simplifying decision trees. Apple's product pages are a masterclass in this.
The F-Pattern
Eye-tracking studies show users read in an F-shape. Put your most important content in the top-left. Navigation, CTAs, and key text should all follow this natural reading flow.