Sometimes it is just a matter of what you offer as a hospital, the volume of people you bring in, and what you do.

Example:

Obstetrics is becoming a major money looser due to changes in the insurance market. So insurance companies how require a hospital who handle's births to also have a surgery center and be able to handle c-sections in order to insure any birthing. The thing is that requires an on call surge and staff and things that previously a lot of hospitals didn't have.

So in order provide that service the overhead just skyrocketed. Many rural hospitals just don't offer it anymore or if they are / are taking big losses to provide the service.

That's just one area.