Fresh start! Reboot! Recycle! Whatever you want to call it.
Sure, the 5% who are good will have to find a real job for 2-6 years, but they can run again next time. It'll keep them from screwing up the economy because they know they will soon be back in it.
It's the best way to stop the corruption, also known as “cronyism.” Government (especially military) departmental heads (not just the Directors) need to be recycled in between every presidential election (straddling both administrations for basic functionality assurance).