I never related invisibility literally. To me, invisibility in design is when the user doesn't figure out the stuff, making all fluid helped by the evident UI.

I never related invisibility literally. To me, invisibility in design is when the user doesn't figure out the stuff, making all fluid helped by the evident UI. That's when the design becomes invisible because is not part of the problem. Tell me if you figure out your doorbell design, you wont because the design is not the problem so the aesthetics of your doorbell, the functioning and other areas become invisible. You just focus on actions.