Progress implies drawing closer to an ultimate goal. Progress in medicine means that we are closer to discovering cures for cancer, AIDS, etc. Progress in diplomatic relations means that we are closer to granting the wishes of every beauty pageant contestant ever: world peace. But some things have no progress, like fashion. You will never hear someone say, “This sweater is perfect. No one ever needs to design another one again, and we can all throw out our old ones, because this is the perfect sweater.” It’s the same with literature, and with a lot of other things. They don’t progress. They just change.