I have evaluated federal employees as part of a business case analysis (I was previously in Manpower Management). Individual performance varies greatly, just like in the private sector. It is due to a myriad of factors: intelligence, disability, attitude, work environment. One examiner's...
Its not the fault of the federal employees. The vast majority of them are honest, hardworking, and put mission before self. I know this from first hand experience. And they are accountable to you; simply contact your US House Rep if you have an issue with their service. Its a fairly easy process...