Again, the DOCTOR prescribe the medicine not the patient. Why would the doctor prescribe unneeded/unnecessary medicine?

I understand the social pressure etc. However, when I go to a doctor I expect him/her to prescribe something that is necessary not just write a script to get me out of the office.

Can much of health care problems be pinned directly on the doctors? I know its unpopular to criticize doctors, but I'm beginning to think that we can only address the health issue by directly confronting the MD's.