From an IM perspective vs EM perspective.
EM -> stabilization, "hi-bye" medicine, provisional diagnosis, temporazing measures. Very heuristic, high volume. Lots of procedures if you want them.
IM -> management. continuity of care, nailing down all diagnosis (eg not just sepsis with AKI and hypoxia, but infectious endocarditis, with infectious glomularnephritis, acute MR rupture, ring abscess, etc etc), definitive management. Much more cerebral at the expense of procedures and volume. Also fellowship options.
People figure this out quickly. I was far more interested in seeing what the hospital course was for an admitted patient than whatever walked in from triage or EMS during my EM rotation. During residency, I hated the mostly low acuity (but minefield fraught) of most EM presentations. Not a huge fan of general medicine wards, but the problem solving was satisfying.