I've worked tons of ERs of all sizes, in 2 different states, and it literally never fails that there are no beds all day, or a bed appears at 1600-1700. The hospitalist goes in (finally) and places orders at 1800. By the time I do any stats that he's ordered and find someone to babysit my other 4 patients (some of whom could be ICU admits or have stat orders as well) and find a tech to help me transfer the patient once we're on the floor, it's 1830. There are ESI level 2's coming in droves by ambulance and flooding the waiting room. The admitted patient has somewhere to go, and we need to flow patients. It's a safety concern.
Additionally, I feel like as ED nurses we're not quite as sympathetic as other floors when it comes to admissions. We don't get to tell EMS "Sorry, no STEMIs right now, it's 1900, you'll have to wait till 1945." I understand that we're all busy but I promise at least on my end it's not vindictive, it's just what happens.