In years past, when HMOs didn’t exist, use of health insurance was fairly straight forward. As a patient, if you had insurance, you could see your doctor when you wanted and as many times as you wanted; your doctor could order whatever tests they deemed necessary, and do whatever procedures they deemed necessary. Patients were happy because they got the care they needed without hassle, and doctors were happy because they could provide the care they felt was appropriate and would get paid for it.
However, over the last several years, such a system became untenable for several reasons: increasing population, increasing life-span, and ever-improving medical treatments that were very expensive. It became unrealistic for all people to be able to afford traditional insurance plans, nor for the government to subsidize health care under this traditional model. That is where HMOs came in.
HMOs provide health care but with several restrictions: patients require authorization (approval by the insurance) to see their doctors, as well as authorization for needed tests or procedures/surgeries; unfortunately, this need for authorizations can create delays in necessary health care for many patients. Presumably, the HMO system, if well-run, would cut out waste and spending on unnecessary doctor visits, tests, and procedures, thereby providing for affordable care for a large portion of the population. Sadly, many HMOs are run by either incompetent or corrupt bureaucracies, thereby compromising necessary patient care in lieu of their bottom-line. That said, some HMOs are better than others, and both patients and doctors must do their due diligence to determine whether or not to participate.