Stalin's dictatorship devastated the Soviet Union in several ways:
1) It imposed extreme control over all aspects of society, removing freedoms and individuality from citizens. Social goods, work, and even personal lives were dictated by the state.
2) It created a climate of fear, as citizens lived in constant threat of punishment for any perceived "anti-state" acts. Millions were imprisoned or killed under Stalin's regime.
3) It caused immense human suffering. Workers lived in poverty and dangerous conditions. Famines in the 1930s killed millions due to the failures of collectivization. Housing and goods were chronically short in supply.