Many patients wonder why so many physicians are retiring.  Physicians often are in training (medical school, residency, fellowship) till they are 35 years of age.  They delay starting a family because they have no control over where their next job is since the process is a blind computer match for their next job.  When they begin their first job, they have high student debt that is often higher than most home mortgages.  After a few years, they wonder why they are not getting pay raises like their friends. 
The AMA has done this study and found that physician salaries actually decreased 1-2% each year when looking at inflation.