Federal supervisors aren’t doing nearly enough to hold poor performers accountable — or keep them from ending up as poor performers in the first place, two chief human capital officers said today. Reginald Wells of the Social Security Administration and Jeri Buchholz of NASA, speaking at Government Executive’s Excellence in Government conference, agreed that managers need to be more willing to take action when an employee isn’t cutting it. Maybe that means retraining that employee to get him up to snuff, Wells said, or punishing him. But a manager might only need to “call it as it is” and let…