Value and outcomes
Consistency
Also calledUI consistency, Design consistency
Similar things looking and behaving the same way across a product, so people can apply what they learned in one place everywhere else.
Consistency lowers the effort of using a product. When every table filters the same way and every destructive action asks the same kind of confirmation, people stop having to think about the interface.
It gets harder as the number of teams grows, which is why it is the main return on a design system at scale.