It's natural to look at your team and readily pick out your top performers, identify your mediocre ones and, of course, sigh with frustration at your worst associates. Obviously, the best ones are your keepers. They make your managerial life easier and ensure that everything runs smoothly. As for those in the middle, frankly, they're your worker bees. They simply get the job done with at least the minimum requirements of the job. Then there are those low performers. They're the banes of your existence. They sap your energy and your patience.