A metro split by highways, foothills and county lines
Someone in Thornton and someone in Littleton can type the identical query and see two different sets of businesses in the map pack. Google weighs distance heavily for local intent, and the Denver area spreads across Denver, Jefferson, Arapahoe, Adams and Douglas counties, with Aurora and Centennial acting as cities in their own right. A company with one address near Cherry Creek often ranks nicely in central neighborhoods and then fades by the time a searcher reaches Brighton or Castle Rock.
Queries that mention places, not just the service
Colorado searchers are specific. They add RiNo, Wash Park, the Tech Center, Boulder County or "near Golden" to what they type, and they switch to broader phrasing when they plan a trip into the mountains. Your pages need to reflect that geography honestly, describing where you actually serve rather than stuffing town names into a footer. That's the difference between a service area strategy that holds up and one that Google quietly ignores.