let me play devil's advocate for the sake of discussion
I work in Surgery at McGill Univeristy. I don't know any doctor who went through 15 years of schooling 'just' for the money. But thankfully, that's an unrealistic dichotomy anyways. It is important to keep in mind that a career-driven doctor succeeds by excelling in patient-care.
To use an extreme example, even the hyper-profitable plastic surgery practices in LA or NY only succeed and are run by doctors who have spent a considerable amount of time educating themselves, developing their business through infrastructure and marketing, and finally making sure that their patients or clients receive the best possible treatment available, albeit at a hefty price. Even if you want to view this plastic surgeon as doing it 'just' for the money, it is very difficult to produce even a hypothetical scenario where that doctor is not obliged to provide the best possible care that (s)he can provide, if only for the sake of their business.
Canada is a good example of this. In Canada, we have a health care system where nearly all medical treatment that one could ever need is covered by the tax payer. For example, I can receive infinite chemotherapy without it costing me 1 penny more than the taxes that I and everyone else already pay. However, despite this model, the private medical industry is thriving in Canada -- people often rather get treated privately (and pay out of pocket, in addition to the obligatory taxes they already pay) because the 'money-oriented' doctors who choose to open these private business (as opposed to working in the publicly-funded sector) can provide superior treatments because it takes money to buy technology that makes more money that buys better technology. By contrast, innovation and 'improvement' in the publicly-funded sector is driven by cost-efficiency (e.g. we are currently looking for ways to increase recovery time after substantial surgeries; this helps the patient, but it also costs the gov't less in follow-up visits). That said, our publicly-funded hospitals are great.
one oversimplified way of looking at it (though not reflective of the nuances and complexity of each model):
private: money-driven doctors, working in a patient-oriented business model
public: patient-oriented doctors, working in a money-saving business model
To use another extreme example, I know very many doctors who have "a genuine passion and calling to heal others" but who simply provide treatment that is less than ideal because they are working in 'rural' areas of Canada, or in poor countries (e.g. Nepal)
by the way, wishing you a speedy recovery
@Dav4 that Ume needs you!