Anyone who has studied art will understand the concept of a focus point. Though, there may be a more appropriate name, you get the idea.
Visualize Monet's _Water Lilies_ - an ethereal blue/green landscape. Now, place a yellow smily-face in the corner of that picture. When you look at the picture now, your eye is automatically going to zoom in on the smily face. It's now become the focus point (and quite an eyesore, I might add).
I hate when I read the descriptions of a room in published modules. I see this all the time:
"You open the door and you see a large chamber, some 100-feet wide, with a vaulted ceiling of oak buttresses. In the corners you see some disheveled furniture and some assorted chests, trunks, broken furniture scattered about, and a few things with dust clothes covering them, concealing their true nature. In the center of the room you see Michael Jackson sodomizing a young boy."
Ok, maybe not *that* example. But replace the latter with "You see a Beholder" or something like that, and you get the idea. The thing is completely backwards. If you opened the door, the details of the room are going to be completely blurred, and all you're going to see is the freaking monster. I see that all the time.
So, focus on the important parts and gloss over the rest. That's what people do anyway.