2.2 Why design systems exist

Typical benefits:

Consistency

The same interaction should behave similarly everywhere.

Speed

Teams can compose interfaces instead of rebuilding everything.

Reduced design debt

Repeated one-off decisions are replaced by reusable conventions.

Reduced engineering debt

Shared components reduce duplicated implementations.

Accessibility

Accessibility behavior can be solved once at the component level and reused.

Brand consistency

Visual identity becomes encoded in reusable primitives and tokens.

Cross-team communication

Instead of saying:

"Use that small gray text under the field."

the team can say:

"Use Text with variant="caption" and color="muted"."

Shared vocabulary is extremely valuable.