Sorry i meant "doesn't compile", which is the essence of open source programs anyway. If that wasn't an issue on OS X there wouldn't be so many porting projects (macports, fink etc). And if you work with non-popular (e.g. scientific) programs that's not even an option.
Compiling software is not trivial, that's why you have macports, fink, etc... Like you have apt, portage, pacmacn... on Linux distros or ports on FreeBSD.
Enthought has binary distributions for the various platforms for a long time.