Why did most experiments with communal living in the nineteenth century ultimately fail?
The reason for this is that these were utopian communities which, by definition, had very radical ideas. These ideas would typically only be attractive to a few people and would therefore be unlikely to last as the basis for a community.
For example, the utopian community of New Harmony in Indiana tried to get by without any private property or money. The Shakers are famous for their strict segregation of the sexes, including their demand for complete celibacy. These sorts of ideas are so radical that it is very difficult to find enough people who are willing to commit to them for long enough to create and sustain a stable community.