I'd be interested to see when actual socialists think the Soviet Union stopped being an effective socialist state and started being more of a totalitarian kleptocracy with a veneer of socialist rhetoric as justification.

I was an early Agile person, starting with Extreme Programming in 2000. It blew me away how quickly a revolutionary approach to the work I loved was turned into a bunch of empty labels and pointless rituals that covered up the same old power structure but provided the useful appearance of change. [1] It's definitely made me wonder what early Russian revolutionaries would think of how the Soviet Union turned out.

[1] http://agilefocus.com/2011/02/21/agiles-second-chasm-and-how...

The Bolshevik coup in 1917 pretty much ended democratic socialism in Russia. Prior to that, workers were forming self-organized soviets (essentially a union government) that, at least from my vantage point, looked pretty much exactly like what a communist government is supposed to look like. Lenin didn't think Russia was ready for socialism yet, so the Bolsheviks seized power away from the soviets and formed a dictatorship. I'm not a socialist (well, I probably am according to today's definition), but if I were I think I'd say that's when the Soviet Union stopped being an effective socialist state.

Edit: just to clarify, this is a brief gloss that leaves out a lot of nuance.

Lenin called the new system State Capitalism and talked about "control, supervision, and accounting" as being the solution to the country's problems [1]. Even Marxists warned about the totalitarian nature of Lenin's project. These essays by Chomsky explore the topic: The Soviet Union Versus Socialism [2], Objectivity and Liberal Scholarchip [3]. Chomsky gives Luxembourg and Pannekoek as examples.

[1] http://marxistsfr.org/archive/lenin/works/1917/ichtci/02.htm...

[2] http://www.chomsky.info/articles/1986----.htm

[3] http://www.ditext.com/chomsky/1968.html

Since Stalin was both an early Russian revolutionary and the nadir of "how the Soviet Union turned out", it's hard to accept the reading of history that says the Soviet Union didn't turn out according to plan.

Considering Stalin's swift elimination of all his political rivals, it's reasonable to assume not everybody shared his political vision.