Idea lives forever. Practice does not.
Think of the books and all the text we've read. The ideas and philosophy by Plato which were written for more than two thousands year are still read until today.
But the manager of let's say a certain company will not be remembered.
Even some of the texts written to convince us regarding the importance of practicality are theorized. Perhaps it is not a fair comparison, because there is certainly no contradiction between theory and practice because theory supports practice and vice versa. We often forget that though things appeared to be contradicting, they actually compliment each other.