Keyboard use reveals how clearly an interface is structured. The order of links and controls should follow a sensible path, with a visible focus indicator throughout. I consider that path while arranging the screen rather than leaving it to a final review.
Dialogs, filters and expanded sections need particular attention because they change the interaction context. The next focused element should make sense after an action. A keyboard pass is also a practical way to find controls that look interactive but behave inconsistently.