The colors draw my eye from across the room. But the WOW factor may become apparent as you get closer. Sometimes it is pattern, sometimes color, sometimes how the subject matter is interpreted.
I remember a quilt I saw at a show a few years ago in Ashville, NC. It was a portrait of a quilter -- she was depicted as an 8-armed Indian goddess. Each hand multitasking with something quilty. The longer you looked at it the more detail you found. Awesome!
Another show I saw a quilt depicting jazz and jazz musicians. Price tag on it was thousands (don't recall exactly) but were I wealthy, that quilt would have come home with me.
Each very different -- but WOW indeed!