Dances of the orang laut

Before a team can know whether an interface looks right, it has to see how the interface actually renders, everywhere it might be viewed.

A test suite can be completely green and your product can still look broken. Functional tests confirm that the code does what it should; they are blind to whether the result looks the way it should.

Every release moves something. A developer fixes a bug in one component, and three screens away a margin quietly shifts because of a shared style. Nobody notices until a customer does.