So, to be a bottom 20 QB, there only has to be 12 better than him. You could probably name 12 better than him yourself...
If you want to bitch about Omar, at least do it when he is off-base. He isn't in this case. We hope Tannehill gets better, but right now he is a bottom 20 QB.
Brady
Brees
Rogers
Wilson
Rothlesburger
Flacco
Luck
Manning
Smith
Rivers
Romo
Manning
Foles
Palmer
Cutler
Stafford
Ryan
Bradford
I pretty much think people use whatever context they want to make a point. I don't so much look at QB's as numbered 1-32 as I do what tier do they fall in. You generally have maybe four tiers. 1st tier is elite and I think you can say four guys are in it, being Manning, Brady, Brees, and Rogers. I will add however two of those four have shown reasons to not chose them if you were building a team today, being Manning and Brady look to be in decline. I'm not as big on Brees as many either, big numbers but is pretty up and down. Rogers is about the only slam dunk. Next you have a large group of guys ranging from guys like Big Ben and Tannehill. These are guys that are considered starters beyond question but vary greatly in things like Luck, Tannehill, and Wilson are young and have their best QB years ahead of them to guys like Romo and Smith, guys who are pretty much who they are. Third group is guys like Palmer and Eli Manning, guys I really don't want on my team period even though they have upside. Last group are guys like Vick and buttfumble, guys considered a quick fix at best.
Every player has his own story too add as well, Wilson playing for the leagues best team top to bottom, Smith playing in a ultra conservative team, Luck steeping in to a roster made to pass successfully, and Tannehill has a team with no real offensive talent other than a quality TE and some pretty good speed receivers. To me bottom line is anyone trying to number them in any way shape or form 1-whatever is just guessing.
And BTW their is no real solid reason you can say half those guys are "better" as a quarterback on individual merit than Tannehill. And there are a few guys your insane if you want them as the quarterback of your team over Tannehill, those being Bradford, Palmer, Smith, and Cutler...Stafford is losing respect quickly as well.