Software engineers often focus purely on functionality, but the user experience is just as critical. Understanding basic UI/UX principles can make you a much more effective developer.
Visual Hierarchy
Use size, color, and contrast to guide the user's eye to the most important elements on the screen. The most critical action should be the most prominent.
Consistency
Consistent design patterns reduce cognitive load. A button should look and act like a button everywhere in the application. Stick to established design systems and conventions.