A) years of experience (vs. teachers who are new to history, or to middle-school grades)
B) knowledge of the content (vs. teachers who have Generalist certificates, or get moved from "9th grade Ancient Civ" to "11th grade Psychology and grade 7 US Geography")
C) quality of administration & staff support (vs. teachers without a mentor and/or suffering an unhelpful principal)
To the last point, here's a recent request on a Facebook group from someone in Arizona:
I've never had serious pushback from administration or parents against my unusual decisions -- to flip the direct instruction and ditch the textbook, for example. Contrast that with the teacher who posted that she got "turned in" by a 2nd-grade teacher whose daughter didn't like getting a quiz about class procedures...and that student was moved out of her class!
Or this poor teacher who travels around the building:
We [veteran educators] would do well to remember those feelings, and help less fortunate colleagues whenever and however we can. Their struggle is real!