Because there are essentially two different CL services in Omaha. A goodly chunk of NW Omaha has the best internet in the area in CL Fiber Optic. I had the Fiber for probably 5 years or so before I moved, and it never went down that I can recall.
Pretty much the rest of the Omaha metro has crappy CL DSL. No matter how much I hated Cox (and I personally don't) I wouldn't buy DSL period. No matter who offered it or how cheap.