I think we have the following consensus.
Tier 1: Shankly, Paisley and Klopp.
Tier 2: Rafa and Kenny.
Tier 3: Fagan and Houllier.
Tier 4: Rodgers
Tier 5: Evans and Souness.
Tier 6: Hodgson.
I like the tiers but still think they can be ranked within those tiers. My rankings with justification:
Tier 1 Managers: Shankly and Paisley (Jurgen needs another League or Cup to move into Tier 1)
Shankly is obviously Tier 1 because he started everything we have today from culture to the iconic kit we wear.
Bob is Tier 1 because he is one of the greatest managers ever, not just of Liverpool but in England and across Europe. He won 20 trophies in 9 seasons. Leagues, a UEFA Cup and our first three European Cups. And he was there at BIll's side from the start of the Shankly revolution. Would Shankly have won as much without Bob? Who knows, I know that Bob won more as a manager on his own.
So for me its Bob Paisley top of the pile and then Shanks.
Tier 2 Managers: Klopp, Benitez and Kenny. Dalglish: We'll never know what Kenny's team might have done in Europe for obvious reasons but I know what they did in England. They took football to another level with Barnes, Beardsly and the rest. We'll also never know what would have happened without Hillsborough. His first time as manager was bookended by the tragedies of Heysel and HIllsborough which took away the chance to shine in Europe and took away his love of the game for a while. A special mention for his second spell when he came back to help heal the scars of Hicks and Gillett. The game at Fulham whne Maxi scored his hat-trick and the away end sang the Maxi song non-stop always brings a smile to my face. If he'd won a European trophy he'd be in tier 1 but there are a few managers where 'could have if...' applies (see Rafa).
Benitez: Rafa - what a man. For a club who have so many iconic football moments he gave us all the iconic moment of iconic moments. I watched the Road to Istanbul on Tuesday followed by the whole final. And then a year later, an iconic FA Cup Final (3-3) with another of those Gerrard moments. Rafa made Liverpool an elite force in Europe again. But tight purse strings under Moores and the shit-show of Hicks and Gillett meant he never won the League.
Klopp: He's on the cusp between Tier 1 and Tier 2 for me. He has some of the drive and personality of Shanks and the managerial nous of Bob. But I think he needs to win another League or European Cup to move up a level.
So Tier 2 is Klopp, Kenny then Rafa (three leagues counts for more than Istanbul for me).
Tier 3 Managers: Fagan & Houllier. Agree on both both of these. A pair of Treble winners. Joe was a great coach and was at Bob's side during his success. He was a reluctant manager and would probably have resigned regardless of Heysel. But his trophies speak for themselves. I'd place him higher than Ged because winning a League and European Cup double (plus a League Cup) is an amazing achievement, regardless of the quality he inherited.
Tier 3: Joe Fagan then Gerard Houllier.
Tier 4 Manager: Brendan Rodgers. I have to agree with this as well. Roy Evans and Souness both won trophies and Brendan won fuck all. But I have never laughed so much with sheer enjoyment at the match as in 13-14. After Hicks and Gillett, the dourness of Hodgson and the brief re-surgence under Kenny's return Rodgers LIverpool felt like a team with the potential to reach for the heights again even if we fell short that season.
Tier 5 Managers: Roy Evans and Souness. Both won domestic trophies but neither hit the heights. Souness won the bigger pot but Roy gave us some great football to watch including the classic 4-3 against Newcastle.
I wouldn't split these two - Evans and Souness on the same level for me.
Tier 6 Manager: Roy Hodgson. Why?... just why?... He was just the wrong man for the job. Never should have been anywhere near Anfield unless he was in the away dugout getting spanked by the boys in red. Some of the worst, dour, shit-on-a-stick football I've ever seen Liverpool play live or on TV. The muppet who had Brendan below Hodgson clearly never had to sit through ninety minutes of his clueless rigid football.
Other opinions are available...