You see it used in all kinds of movies and television shows, usually the police drama type.
The good guys and the victim are on one side, the suspects on the other. Each are nervous for different reasons: one thinks "Can I be seen?" and the other "Will I be recognized?"
It's called a two way mirror.
We have them in ChurchWorld, too. And they are used a lot of different ways.
How about Simplicity/Complexity?
On one side, we should strive to make everything as compelling, seamless, and simple as possible. The way we welcome guests (facilities, processes, people); how we navigate inside (wayfinding); the worship experience (flow, communicating The Big Idea, call to action); gathering information (connection card, digital system). You get the idea. We want everything our guests and participants see to be clean, elegant, simple, and logical.
Then there's the other side of the mirror - the darkened room of reality where it's often chaos, confusion, last-minute changes, and sometimes flat-out failures. It's the hundreds of details that go into a simple print piece. It's weeks, if not months, of planning and work to make sure the worship experiences go smoothly. It's arriving early to set up, clean up, polish up, and look at your absolute best - because you only get one chance to make a first impression.
Guests and attendees don't need to see the complexity of the systems designed and implemented to give them simple, powerful, life-changing experiences.
But they wouldn't have those experiences without the complexity.