Sorry but your response is a No True Scotsman argument. It is understandable why irrational behavior applies here - sunk cost, nobody wants to have the bad news

Sorry but your response is a No True Scotsman argument. It is understandable why irrational behavior applies here - sunk cost, nobody wants to have the bad news of letting a new hire go, explicit objective setting may require there to be new hires. These will generally apply to any manager. Unless the new hire is clearly stepping out of bounds or extremely negligent, it is going to be a slow process.