One of my students asked for information about what to look for in a writing group. I feel like something of a connoisseur of writing groups, having been in four: Western Women Writers, Western Union Writers, Melbourne Writers Group and SuperNOVA (formerly NOVA). Each of these groups has been different in structure and in what they offered me. Some have been a better fit for me than others, but what is important is finding the group that offers you the best fit.
You need to decide what you want out of a group. Do you want a group that critiques your work -- that tears it apart and analyses it and says what's working and what isn't? A good critiquing group is worth its weight in published manuscripts. However, a critiquing group is not for everyone. Some people are not robust enough to take honest criticism, whether they are new writers or experienced. I've seen published writers come and sit through a critiquing session at Western Women Writers and quaver at the level of criticism. If you think hearing negative comments about your story may destroy your confidence, then you're not yet ready for this kind of group. Find another type of group, one that's more encouraging, until you're ready.
There is more than one kind of problem that arises in a group with a member who is not ready for workshopping. Firstly, it can destroy that writer's confidence -- especially if they're a new writer. (This can arise from both constructive and destructive criticism -- more on destructive criticism later.) The second problem that can arise out of someone not ready for workshopping is when they feel compelled to argue against every suggestion made. Nothing annoys workshopping members more than someone who is not receptive to comments. The workshoppers wonder why they have wasted their time when they could have been writing! Another form of this is the writer who seems to accept criticism but never learns from it, and continues to make the same mistakes, or even worse who re-presents the same piece over and over with virtually no changes, and all the workshopping suggestions ignored. (Actually, there is something that annoys workshoppers more: when the critiques are all delivered and the new member sits back with a smug grin and says, "Well, actually, you're all wrong, because that story's already been published." Don't do it. It's a sure-fire recipe for ending what could have been a beautiful beginning.)
Some groups are more supportive than critical. Western Union Writers is like this. If ever there was a group suited to the nervous beginner, it's this group -- and it offers plenty for more-experienced writers too. Writers take their work along and read it out loud and the the rest of the group offer gentle criticism and lots of encouragement. It's a great way to practise your reading-aloud skills, to network with other writers so you don't feel so alone -- the writer-in-the-garret syndrome -- and they do run workshops and have a writers' retreat once a year. Great stuff if that's what you're after and many writers are. And that's fine, but if you're really serious about getting published, at some time you're probably going to need a good critique group.
A professional-level critique group will give you far more criticism than pats on the back -- professionals hardly ever pat each other on the back. What they're after is ways to make this story the best story it can be, not an ego-stroking. If you want to be a writer you should shelve that ego right now! (Shelving it is good both to stop you getting a bighead when things are going well, but also to keep you from despair when they're not.)
A word about destructive criticism, because I said I'd come back to it. Destructive criticism helps no-one and shouldn't be tolerated. Ever. If you do want a critiquing group, make sure the criticism is constructive -- ie that it helps you by suggesting ways you could fix things. Years ago, after a masterclass at the Melbourne Writers Centre, I had one writer who reacted badly to a critique I gave on his story (which I thought worked very well overall) by sledging a piece of my work. He started out with, "I wish I could say something good about this story, but there was nothing." Luckily for me, the workshop convenor, Jack Dann had plenty of good things to say about it.
Clarion is an intensive workshop experience, and there's stories of writers who go and never write again. I know afterwards my own output dried up for a while, but I was suffering burnout as much as anything. I went into Clarion at the end of teaching,and in my six weeks living in a student dorm with no airconditioning in Brisbane's hottest summer on record (at the time), I wrote six stories (including a trunk story I wrote just before going up) and one collaborative story, 50,000 words of a journal, worked a little on my novel, critiqued over 500,000 words and then went straight from Clarion into a teaching round that had already started. Too much. But I can see why some writers never write again: it's a hothouse of emotions as creative energy is sapped by the relentless pressure, and the crits are hard (but fair). It's like the most intense writers' group you could ever imagine, but, yeah, you have to be ready for the criticism!