When you first hear about the wiki, your reaction is predictable: "Anyone shall be able to edit any page?" and "Even my text?". Anyone is quite sure that it can't possibly work. But the empirical fact is that it has worked for thousands of users over many years.
Wiki and Community
People worry that someone will come along to delete their valuable contributions or will write random garbage all over pages. This indeed can and does occasionally happen, but as soon as any of the wiki's community members notice the
problem they restore the page's original contents from the previously archived version. After continually having their "work" removed, the offending individual usually quickly gives up and goes elsewhere.
A more common problem is that no community consensus emerges, possibly because the community is split into opposing viewpoints on some issue. Here's where a policy like the Wikipedia's "neutral point of view" can help, by allowing folks to work together to express each of the viewpoints, rather than resolve the issue to a single correct one. This requires a real sense of community and a respect for each other's beliefs.
Another reason that discussions do not resolve is that the community is exploring a new area and just doesn't know enough yet. In that case, the various discussions will just sit there and be a reminder that the issue is still open. As individuals (and hence the community) learn more, people will add to the discussion
and reorganize it.
Building a Community
People like to found online communities for their special interests or favourite projects. Communities usually develop slower than their founders expect, so you need a good amount of patience and sturdyness to get it going.
One barrier is the open nature of the wiki that is unfamiliar for many people. Users can be afraid of what will happen to what they write or unsure of what type of contributions are accepted. The tone set by the community will either encourage or discourage new folks to join in. Once someone does contribute and begins to edit wiki pages, they gain a feeling of empowerment and often develop a vested interest in overseeing the wiki as a whole.
A wiki is a community effort and each community develops its own culture. In general, the sense of working together to build a better understanding seems to encourage people to be more polite then many other Internet activities do. Maybe this is because on a wiki flames and spam can be easily deleted, while the constructive comments are expanded and grow.
Coming to a common place, sharing a vocabulary, and working together over time on common goals all help to make the people using a wiki into an actual community.