#1 Arrigo Sacchi

Pep Guardiola is considered by many as the best manager on the planet today, but the Spaniard himself admitted that he learnt the foundation of his managing style from Arrigo Sacchi.
At first, you don’t succeed, try and try again, but for Sacchi, he tried and failed. Instead of wasting his time at a profession he clearly wasn’t good at, Sacchi tried his luck as a shoe salesman before eventually getting into management. Sacchi wasn't even good enough to make it as a semi-pro down in the Sunday leagues in Italy.
A man that couldn’t even make it as a semi-pro became the first man to win back to back European Cups. Sacchi was a below average player but undoubtedly a great manager. The Italian managed 284 games at the top level.