projects could cost 10 percent of what they do and still provide 85 percent of the functionality.5 I hereby dub this “Byrne’s Law.” It’s not that that final 15 percent of the functionality shouldn’t ever be built—the software can and should eventually support edge cases. It’s just that trying to have it all done by launch, before you’ve had the chance to work out the kinks with the core workings of the project, will often tank the operation of the other 85 percent.
