Given the economic gap between the soviet union and the western world, to what extent did the goals of collectivization and the five-year plans justify the tremendous cost borne by the soviet people?

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

the reason is because of the red army and the allies

the war started at different times