Working for the government is not like working for a private sector company. There are some who would like to see that change, and perhaps over time some of the conditions that currently separate the two fields may be adjusted. For now, however, the distinctions exist.
Those with solid experience in employment law would likely agree that the one factor that divides government work from most other jobs is that employees enjoy particular rights of due process. These have their roots in the U.S. Constitution and Congress decided to apply them as a way to reduce political influences and promote more efficient conduct of government business.