The answers below are helpful. The limits were made so another King George lll mishap wouldn't happen again... Checks and balances limit a government's power.
It is important to limit a government's power so that one branch doesn't overthrow another and there will be equal balance among all braches of government.
The five-year plans do not certainly justify the tremendous cost borne by the soviet people. This is because the plan only brought glory to Stalin but did not improve the welfare of the people as is reflected in the economic gap between the Soviets and other western democracies