Sometimes a player like Brocchi is better than Hernanes...
But a player like Brocchi you can build it up in your own academy picking from the youngs and trusting them,take Onazi for example,which already has more quality than Brocchi and its in his 20's...
A player like Hernanes is a gift.
Quality is harder to build up compared to mere athletic skills/energies and its easier to fit in whichever team,has a larger impact (needless to say,media,supporters...even your opponents...if you have such a talented player your team does an effective jump besides how he does really play during whole season) in a match outcome and may lead to successes which would've been impossible to achieve without.