We talk about "right" reasons, but what the hell are "right" reasons and whose definition of "right" are we using?
There are many reasons one could have for doing Medicine, but as long as one performs his job properly, are there really "right" or "wrong" reasons for wanting to become a certain thing (e.g. doctor...etc)? If there are certain "right" reasons to wanting to do Medicine, are there such "right" reasons to wanting to do Engineering or Law or Education or Arts?
We can't really discuss right or wrong reasons because they are things which are abstract, there are certain things which are outright wrong - e.g. wanting to do Medicine to kill people, but for the majority, there is a lot of overlap depending on what is "right" and what is "wrong".
I just think that as long as you act morally, you aren't doing anything wrong. If you were treated by a doctor, do you really care whether that doctor did it for money, for fame or whatever? No - doctors, like everyone else, have a job to perform and they should perform that job professionally, the same regardless of what their motives are - as long as that is the case, this is a redundant discussion.
What we should be discussing is - do all who end up in Medicine truly want to do Medicine - that's probably a more interesting discussion.