Don't Make Me Think, Role of Colour in UX

In Don't Make Me Think, Steve Krug introduces the concept of self-explanatory design. The idea is simple: when users land on a page, they should immediately understand what it is and how to use it; without effort or confusion. There should be no need for what Krug calls “cognitive ditch-digging.”

When applying this principle to visual design, especially color, the goal shifts away from decoration and toward clarity. Color is not used just to make a page look appealing; it is used to remove ambiguity and guide users naturally.

The Reservoir of Goodwill

One of Krug’s key ideas is the “reservoir of goodwill.” This represents the patience users have when interacting with a product. Every time they encounter something confusing—such as a button that doesn’t look clickable or a color that carries no clear meaning—that reservoir begins to drain.

To preserve this goodwill, visual design must support usability:

• Visual hierarchy: Color should clearly indicate what is important. If everything is bright or competing for attention, nothing stands out.
• Consistency: Actions should always look the same. For example, if a “Submit” button is blue on one page, it should remain blue across the entire application. Changing colors for the same action forces users to stop and think.

The 60–30–10 Rule in UX Design

Although Krug does not specify an exact number of colors to use, modern UX practices—aligned with his philosophy—recommend keeping the color palette limited to maintain clarity.

A common approach is the 60–30–10 rule, which organizes colors as follows:

• 60%: Primary or background color (usually neutral)
• 30%: Secondary color for structure and layout
• 10%: Accent color for key actions and highlights

This structure helps create a balanced interface where users can easily identify priorities and actions without confusion.

Conclusion

Krug’s philosophy emphasizes that good design should feel obvious. In terms of color, this means using it deliberately to communicate meaning, reinforce consistency, and guide user attention. A restrained and purposeful color system reduces cognitive load and helps users interact with interfaces effortlessly.