Visualizing all the discrete states an application can be in will make your design systems better. This in essence is the most pure form of a ‘living style guide’ and will help your design team develop a cohesive and modular design system.
And from the recommended reading, Pure UI:
The design and creation of an application serves a clear goal: the creative representation of some data a set of users are interested in.
States for network failure, stalled loading, failed server-side requests – these things might rarely happen, but at some point they will happen. I want the experience in any app I design to be as helpful and familiar as possible for people who encounter these edge cases. And to do that, it means considering these states early and not as hurried, band-aid after-thoughts.
The UI is not done until I understand what people using an app will experience in all possible states. But this requires a much more rigorous process than anything I've ever done. As always, there's a whole lot left to learn.