If I take 50 women and successfully encourage them to join a project because everyone is nice and they will feel like they are frolicking with bunnies, but they actually have a contradictory experience — then this is bad.
I cannot magically take away the bad experience that they had. I cannot turn back time and make the sexist joke or come-on go away. I cannot turn back time and make the negative stereotyping alienation non-existent.
She goes on to discuss the problems of low hit rates (i.e., the percentage of people exposed who become participants in a project) and sticky memories. She argues that increasing exposure won’t help if most of those exposed, however otherwise likely converts they may be, are more or less permanently turned off by, e.g., a sexist incident. (And, of course, it need not be sexist per se. If we are trying to recruit women and women receive enough hostility and react in certain ways, then that will do the job without anyone having to produce specifically sexist content.)
(I’m generally of two minds about boot camps or other initiating challenges. They clearly have some virtuous effects, but are often alienating to a significant percentage of people coming through (and brutualizing!). The sorting function is, of course, a touted benefit. (I.e., the alienated people drop out.) They often seem time efficient and do have a bonding function.)
One point I didn’t see emphasized in her post is that the high turn off might make it difficult not just to rerecruit from the pool of the alienated, but also to recruit fresh people. There are several mechanisms for this but consider two prominent ones 1) you’ll tend to have fewer of the target pool in your group which makes it harder to recruit, period, and 2) negative word of mouth or negative reputation.
So there’s a huge difference between a low hit rate where the non-sticky people are saying, “Oh, it’s a great community but I’m not so interested in the project.” and one where they are saying, “I wouldn’t join that community if they gave me rainbows made of gold bricks.”