Note to Business Leaders, Present and Future

Don't tell your employees to be excellent if you're willing to accept mediocrity. It's a total slap in the face when you tell your employees to create high standards, then when they complain about repeated failures to meet those high standards, you tell them to accept less than those high standards because it's good enough.
If it were school, it's like a C is okay even though everyone is capable of As or A/Bs.
Why should I tolerate less than the best when I know people are capable of doing their best?
And how bitchy do I end up looking when I enforce standards that you didn't care about to begin with, even though you told me you would support me. You break your word, you lose the employees you can least afford to lose... those that are crucial to your overall success.