The Western and the liberal consensus on Joseph Stalin:
Stalin was an evil autocrat who seized all power from his people to establish a brutal and murderous authoritarian regime.
Stalin in reality
Stalin: Please, let me resign in peace. This is the fourth time I am submitting my application.
The central comittee: Dear Comrade Stalin, we have rejected your request for the fourth time. See you at work tomorrow.
By theory, having one leader over a long period ensure more stability and completion of long-term projects. It should have similar reason as the reason why the United Kingdoms and United States suspend election during the second war between the European empires.