Point out to me the "bad" teams that are moving up out of desperation. Go back and look at the history. Normally, it's teams that think they have the rest of their roster in place, besides a rookie. Normally I like to go with a 20 year outlook, but I wasn't able to find a chart quickly enough compared to this.
http://www.footballperspective.com/teams-traded-up-for-a-1st-round-qb-16-times-from-2005-to-2017/
2006: Broncos were 13-3, still traded up for Cutler... didn't work out.
2007:
Browns were 4-12, were considered an up and coming team with their FA class but faltered with Charlie Frye, traded up for Quinn... didn't work out, but the team was a winner his draft year, with DA at QB.
2008: Ravens had a bad year at 5-11, but were coming off of a 13-3 campaign a year prior. With Willis McGahee, the only glaring problem seemed to be QB... they traded back and then forward again for Flacco... which worked out.
2009:
Buccaneers went 9-7, traded up for Freeman... didn't work out.
2009:
Jets went 9-7, traded a #1, #2, and three solid players for Sanchez (backing up the dump truck)... didn't work out.
2010:
Broncos went 8-8, traded up for Tebow... didn't work out.
2011:
Jaguars went 8-8, traded up for Gabbert... didn't work out.
2012:
Redskins went 5-11, traded 2 1sts, and a 2nds
(!) to move up four spots for Griffin... didn't work out.
2013: No trades up.
2014:
Vikings went 5-10, traded up for Bridgewater... didn't work out.
2015: No trades up.
2016: Broncos went 12-4,
won the Super Bowl, traded up for Lynch... didn't work out.
2016:
Rams went 7-9, traded two second round picks, and a third in 16. Plus another first and third in the 2017 draft
(!!) to move up for Goff... undecided.
2016: Eagles went 7-9 after 10-6 the year before, traded two players to move up to 8, a third and a fourth in 2016, a 2017 first, and a 2018 second
(!!!) to pick Wentz... undecided, since his backup won them the Super Bowl, and he's got an ACL tear.
2017: Bears went 3-13, traded up for Trubisky... undecided.
2017: Chiefs went 12-4, traded up for Mahomes... undecided.
2017: Texans went 9-7, traded up for Watson... undecided and an ACL tear.
So... in 15 instances of trades up, only 7 teams were under .500. Only 4 were "bad," meaning not hovering around .500.
The vast majority of teams are moving up because they think the last piece to their puzzle is the QB - and only one of them actually hit.