Mourinho and Pep have been lucky for reasons that many of us sure do understand. Simeone and Klopp have achieved a lot with very little, that is what makes a great manager for me.
Tony Pulis must be up there with the best in the world then surely?
How successful have Barcelona been without Guardiola?
How successful have Inter, Porto or Chelsea been without Mourinho.
Nowhere fecking near as good as they were with them, that's for sure. Would they have won what they did with Crystal Palace? No they wouldn't. But plenty of other normal good managers have tried to follow them at their clubs (Villanova, Martino, Benitez, Scolari, Vilas-Boas, Ancelotti) and none have come close to replicating their success. So apparently it's not that easy to just stroll into a top side and win everything, else Chelsea, Inter, Porto and Barcelona wouldn't be so much worse without those two than they were with them.
So you have to manage in other countries before you can be considered great?
No, you need to win European Trophies.
Klopp's brilliant so I don't particularly enjoy diminishing his achievements because I'd love to have him here at United. That said, plenty of smaller clubs have won the Bundesliga (Wolfsburg, Stuttgart, Werder Breman, Kaiserslautern) when you have a league where there's one superpower and then a load of teams on a similar level then lots of random clubs will win the league when Bayern slip up. Which is essentially what happens in the Bundesliga. Bayern win most of the time, occassionally they're in transition or hire a duff manager and someone else wins. That doesn't make Felix Magath the best manager in the world, just like it didn't for Thomas Schaaf (Breman) or Armin Veh (Stuttgart).
There's also been plenty of other smaller clubs to make UCL finals too (Valencia, Porto, Monaco). Him getting there was a fantastic achievement no doubt, but Hector Cuper wasn't the best manager in the world when he took Valencia there and neither was Deschamps when he did the same for Monaco.