Because the organizational forms of the left are nearly always counter-revolutionary. The organizations and their management should be destroyed and we should reach out to their supporters, members, or rank and file.
In the left I see a lot of people with no institutional power trying to do something they think is good, and an elite managing and channeling that feeling to amass power to themselves for their own purposes. The organizational forms of the left are about controlling the righteous indignation of a dominated population.
'Society' is not synonymous with a population. Society is a thing that you are accepted to or rejected from. Something with an inside and an outside, a center and a margin. Under the social relations of Capitalism, society is a part of the problem. It should be attacked, disrupted, subverted, and ruined.
I see myself as being on the left, but I recognize that there are a lot of pissed off proles out there who aren't left or right because they know that no one is talking any sense for how to get out of this current bullshit.