I have mentioned before that I see a LOT of bureaucratic waste with insurance filing.
Claims are returned for the most minute mistakes because no one's minding the store.
Someone sitting at claims all day prefers to hit DENIED and send it back, than search for a wrong digit on the same page, be it a date, an address or a zip code. Filing requires a lot of training on both ends and is hard to find. Obama's move to integrate all electronic filing will increase the productivity and reduce costs.

One main provider I know has changed companies and refuses to let us inform their customers.
Another has changed their mailing address and refused to inform the USPS of their new address. This allows them to push the claims another 60-90 days out. Think of all the interest on that money sitting in the bank!

Doctors on the other hand (at least the more unsrcupulous ones), will suggest unnecessary procedures to their patients just so they can BILL their insurance companies and have that extra money coming in. Patients are managed like cattle through a shute, and made to worry unnecessarily. Although in some circumstances, testing is done to protect the doctor from lawsuits in case of illness or disease; the patients are being "worked" through the system.
You should see the thousands of medical codes the doctors have to use. It's BIZARRE.
And heaven forbid, it doesn't match with up with the thousands of diagnosis codes on the other end.

Whoever rigged the system, knew what they were doing. I'm sure they got paid very well doing it.