It's subjective, and I don't agree he is the most complete manager of all time, that is only determined by the trophy count, but what I do feel is that he is the most 'human' of all managers we have seen, because:
1) He realizes that losing is actually part of the journey and you should always have hope - we have witnessed this multiple times - we lost 3 finals before we won the CL with him. But they were very memorable moments, remember him singing with the rock band after our first CL loss to RM ?
2) The teams that he has managed in his time from season to season is so much an expression of feeling on the pitch that I can only describe as a fan as being my own emotions during a game, its fucking weird, I found myself frustrated with certain games, and Klopp makes that change that I would have wanted more times than any other manager in living memory.
3) Those moments where he comes on to the pitch to celebrate with Alisson - you won't see other managers do that like he did, or that interview he gave after we drew with WBA - like he was almost saying "why do they give a shit, when they are getting relegated.." - and later realized he was angry and talking shit. He knows what he looks like when angry and says shit. Also those interviews, - remember the first 4-3 win against City at Anfield and he comes up and says "what the fuck was that !!!!" - LOL some great moments.
The amazing thing is - despite him being so human - the 'normal' one as he announced himself, he beat all those other elite managers, and has won everything for this club, and Yes he connected with the people of Liverpool just like Shanks did.
I am going to so miss this guy for mainly the laughs he gave us, and no matter we lost - you always felt with him things would improve. He connects with fans and his players equally.