The collective and individual level of intelligence here at the site. Also, the sense of community based on a real generosity regarding sharing knowledge in the interests of a better and more competitive game. Here is part of why that is important to me.
I have worked mainly in two areas for the past 25 years after high school and college and various factory, taxi driving, car parking, warehouse and bookshop jobs. One is the labor movement as a labor organizer and contract negotiator. The other is as a college professor once I had finished my Ph.D. The past 20 years I have almost exclusively, except for a few consultant/researcher jobs, worked as a professor. When among ordinary workers as a union staff person, I saw ordinary people take enormous risks to help each other fight for better conditions. Their job was all they had, but they would risk it to help get an unjustly fired co-worker rehired or to improve conditions for co-workers and friends that had particularly bad or dangerous conditions.
I have never, in 20 years, found that spirit in academia. So while I LOVE teaching, and learning from students, reading and talking about books, ideas and real world events, I cannot stand that aspect of universities. Ideally, and across professional life to a great degree people do let each other in on some of our research findings, or provide an insightful analysis. But often there is a guarded caution to hang on to knowledge as if it were one's private property.
The irony is that here on WIS the object is to win. But any good chess player will want a competitive opponent or the smarts they have for the game are pretty pointless. Workers share knowledge on the job often at almost any job, in part because it is in the interest of all to know how things work, and makes work more bearable to understand how one's work fits in to the larger picture.
But that does not always happen in the fields I work in professionally. As a graduate student in the 1980s in NY I often found professors used what they knew to try to bludgeon grad students into submission in classroom discussions, or tried to get students to do their research for them, or else, on at least two occasions that happened to me personally and an especially serious one that happened to a fellow student, stole the original work students were doing to claim as their own.
Here, people give credit to others for their insights, and compliment each other often. They let others know how the SIM works, what normalization is, some tips on drafting. Not to the extent of giving away every competitive advantage of course, no one would expect that. People should do their own work to develop their own strategies. But to find out what strategies others employ, often all you need to do is ask them, or read the forums.
In my line of work, this is called a "commons". A common good - high quality competition - that is seen to be in the interests of all, not owned by anyone, but managed by informal, self-organized means in an efficient and effective manner.
I would have found graduate school a lot easier to deal with if I had had something like WIS to provide me an outlet for other, intelligent company and interests.