putz putz:
Before I dive into this I just want to say that I no way support Hitler or Mussolini.
Hitler- From the background of a poor student with limited potential. Rose to lead his party in 1921, lead a failed coup in 1923, be jailed, be released an rebuild his party, become a dictator by 1933, rebuild the Germany economy/Army/Navy/Air Force, have world powers bowing down to him by standing by as he annexed Austria and Czechoslovakia, invade in 1939 and own most of Europe by the end of 1942.
And how was he able to realize his Lebensraum? He wasn't able to address his the Judenfrage. He never was able to establish a true Volksgemeinschaft. He wasn't able to control his state without the Gestapo. He wasn't able to solve Germany's economic woes without rearmament, conscription, or slave labor. He wasn't able to establish a European hegemony. He wasn't able to abolish Bolshevism. He wasn't able to hold Europe or stem the Allied tide. Nor was he able to maintain his 1,000 year Reich.
Sounds like he wasn't able to achieve or maintain many of his basic goals, desires or ideological tenets.
$1:
Mussolini- Injured in WWI, always into politics, became Italian PM in 1922(?), had Italy turned into a police state by 1927, brought Italy out of a recession, mass territorial expansion of Italian lands until the early 40's.
And how was he able to reestablish the Roman empire? He wasn't able to persuade his people without a police state. He wasn't able to avoid massive military disasters. He wasn't able to hold power and he wasn't able to dodge a partisan execution or a subsequent hanging from a meat hook
$1:
Regardless of how it ended and how horrible both were, both had to be "able" leaders to accomplish what they did.
Yet, the weren't able to establish or maintain many of their core goals, but were able to leave their respective countries in far worse shape than when they arrived as leaders.
CKA Uber 
