Its a sad reality. You design a great set, but all you see when you watch the film is the set dressing. It happens alot. It depends on the setting, the scenery and the way the film is being shot. Its one of the perks to being a Set Dresser: Your work is the final layer.
It happens more on big features than on small films and TV, because there is more money spent, bigger sets, extra scenery created, more footage shot, and more that gets edited out. Paint suffers from it alot, often spending days on a finish that gets covered up or lit out.
Sometimes it works the other way. Sometimes the least interesting part of the set gets all the focus, to your dismay, or the most unlikely set dressing gets a close up.
Always good to know ahead if possible: What's the money shot?