it just doesn't happen in the NFL.
People need to stop calling for Marc Ross to be fired - it is 99.9% not going to happen until after the draft.
Scouting departments are neck deep in 2018 evaluations right now.
A new GM does not come in, no matter if he is hired tomorrow or the day after the season ends, and fire the scouting department.
Scouting departments are overhauled immediately after the draft. Like it or not, that is just the way it is.
https://nypost.com/2015/05/04/maccagnan-cleans-house-on-jets-scouting-staff-after-draft/
http://www.chicagotribune.com/sports/football/ct-bills-firings-nfl-draft-20170430-story.html
https://www.stampedeblue.com/2017/4/30/15493488/report-colts-fire-director-of-college-scouting-make-other-scouting-department-moves-chris-ballard
http://www.tennessean.com/story/sports/nfl/titans/2017/05/01/major-changes-titans-scouting-department-two-days-after-nfl-draft/101156696/
https://247sports.com/nfl/philadelphia-eagles/Bolt/Report-Eagles-fire-two-scouts-immediately-after-draft-52581413
https://www.freep.com/story/sports/nfl/lions/2016/05/02/detroit-lions-scouting-department/83831952/
I also think some outsiders will come in and make recommendations based on whatever JM wants the team to look like starting 2018.
The GM can set the priorities (who really believed "the best player available"?) within a position, e.g high character vs demonstrated performance, as well as which positions to focus on. (Maybe OL?)
As others have said, the time to weed out scouts is immediately AFTER the draft.