> To understand why one team can meet all user's needs, learn about Wikipedia or the Linux kernel. The kernel supports many filesystems, and many other methods of extensibility, but the code is shared. Some want to run it on cellphones and some want to run it on supercomputers, and they've done it in one codebase. Stop me if you've heard any of this before.
I already mentioned previously in this thread "there is a lot of diversity and there are very few high-profile exceptions where one project was able to fulfill the needs of everyone."
Linux kernel is almost an exception, though not even fully. Or why do you think that Debian GNU/kFreeBSD exists? Of course GNU/kFreeBSD does not satisfy everyone either. Some people call it a toy OS even.
Wikipedia is the largest online encyclopedia, but that doesn't mean it satisfies everyone. Their crowdsourcing model is great for accumulating information. It is not so great if you depend on the correctness of a particular piece of information.