Marxism resonates with many people on a moral basis. "People working together instead of against each other; everybody sharing with everybody; equality; no beggars living in the street while millionaires dine of caviar" -- it's in fact an extension of New Testament morals which have been ingrained in Western culture for 2000 years. It appeals emotionally and feels right and just, so some people decide it is the way to go without any considerations of historical failures or practicality.
To this day, GDR fans point out that while there were far less consumer products available in the GDR, nobody had to starve, nobody lived on the streets, there was no unemployment and a very low crime rate. This is true.
Jugendwerkhof Torgau was also true. The GDR was massively unforgiving towards people who refused its blessings. A punk or hippie who actively chose to live as a vagrant subverted the state's fundamental dogma -- that every human being knew nothing greater than working shifts in an aluminum foundry, living in a highrise apartment block and practicing folk dances with the Worker's Folklore Group --, so he had to be re-educated. Methods were brutal.
Margaret Thatcher once remarked that socialists had the problem of running out of other people's money. Not very precise -- because the Eastern-Bloc Nations' state banks could print arbitrary amounts of money. What they
did run out of were ways to make people work. As mentioned above, the central dogma was that people would actually love factory work once factories were nationalized. They didn't -- most types of industrial work probably aren't very self-rewarding. In order to make people work quickly and efficiently, you sort of need the carrot and the stick. Capitalism does just that: The carrots are raises for reliable workers, the stick is unemployment. This method of motivation seems to be very efficient, this is likely the main reason capitalism succeeds.
This fact -- that for many jobs, people need to be motivated with a reward/punishment scheme -- rings uncomfortable to many: Another reason why Marxism still has a number of adherents. Wouldn't it be nice if work could be made so pleasant and rewarding that employees are content with working just for the greater good? Well, it is kinda hard to make building roads, cleaning the streets, building cars on an assembly line or growing potatoes sufficiently pleasant and rewarding.
My parents once visited a family in the GDR. After dinner, the family's mother said: "And now for something very special and delicious!" My parents wondered what it could be. What she brought out was a small, dry, shrunken orange. "A very special treat! From Crimea Island."