Add new value: Apprecation. You can write articles for Wikipedia, but two minutes later someone can come along and completely revise everything. On one level that's great. It makes it very easy for people to combine their talents without even knowing each other.
On the other hand... say what!? I can study at the library, pour hours into research, collect all the important facts, and condense them into a carefully edited easily readable article... and someone with no expertise can swap all the copy for the latest urban myth... or with the latest political rant. I can be a world renowned expert in a subject and someone who wants to pull a prank can trash my work? In extreme cases, Wikipedia allows their editors to recover from major disasters. But do you feel appreciated for your time? And your effort? Knowing that, do you think anyone writing for Wikipedia is putting in that kind of time and effort? Do you want to be an editor for Wikipedia?? You don't have to look at articles as they come in, sure, but when someone trashes an article, you have to go back and fix it. And then someone trashes it again, and you have to fix it. And then someone trashes it again... and again... and again... Do you feel your time is appreciated?
We think that Wikipedia's system is very noble, but it's completely user-centric. While usabilty and service are important goals, the very people contributing to make the website a success should not be the sacrificial lambs bleeding to make it happen. A well built website should be easily maintainable, and once something is well-constructed, no one should have to put the sand castle back together everytime a bully comes along and knocks it down. Sand is not good for building, build in wood, or brick, or marble so the structure can stand up to the demands that are placed on it.