Imagine you have computer running Fedora 19 and you use it for daily tasks. Imagine you are happy with it, especially when you do run yum update (sic). Now imagine you decided to upgrade your bellowed, happily running system to the next major version.
Sure, you head directly to FedUp site, assuring you are running the latest version (because they messed up previous versions which could render your system unbootable), and with the fingers crossed, you fired it up.
Now imagine, after a half an hour, you get this message:
WARNING: problems were encountered during transaction test:
libvpx-devel-1.2.0-2.fc20.i686 requires libvpx-devel-1.2.0-2.fc20.i686
Continue with the upgrade at your own risk.
More than fifty years of computing and research in IT field, with all sorts of methods, algorithms, object oriented, dynamic, functional and what else languages, and resolver figured THAT out?