Some potential negatives of ER practice.
1) usually you are employed or with a large group practice, so not as easy to "do your own thing" or "run your own show"
2) greater percentage of mean/difficult patients vs. most other specialties because the ER has to take all comers, plus gets the folks on drugs/EtOH first before any other doc sees them
3) higher percentage of patients with "entitlement mentality", most likely, because you'll get some folks who could have waited until tomorrow to see their primary doc for some minor ailment but chose not to, and you get a higher percentage of folks who aren't paying for their care (either b/c they can't/have no money or are on Medicaid, etc.) and may not appreciate the difficulty of what you do
4) ER docs feel they are trained to take care of trauma and other emergencies, but also end up seeing a lot of routine/primary care stuff in some cases
5) having to call other docs/hospital services to "beg" for admission of some patient if the doc/hospital service doesn't want to accept the admission
6) sometimes having to beg a consultant/service to come see a patient if they don't want to
7) I have heard many ER docs complain of "customer service satisfaction surveys" being given out to patients and then hospital administrators coming back to harrass the docs who didn't do that well, even if the reason was the patient had unreasonable expectations or was drug seeking, etc.
8) along with primary care offices, the ER sees a high number of "drug seeking" patients who come in the ER wanting narcs or benzos and may get mean or threatening if they don't get them
9) no patient continuity (could be a good thing, depending on your persepctive, but you also don't get the gratification of a "thank you" most of the time and sometimes don't get to find out "how you did")