How does the civil service system provide for persons to be evaluated fairly for federal jobs or for promotions?

How does the civil service system provide for persons to be evaluated fairly for federal jobs or for promotions? Is this an effective system?

The civil service system is an important part of the way in which the federal government fills positions from top to bottom in terms of the federal bureaucracy. One of the most critical ways in which the civil service system  ensures the quality of hired employees of the government is through the merit system. This is the use of testing, both standardized and written, to make sure that candidates for given jobs meet a certain level of ability and education in order to perform their duties well. The civil service system itself was created in 1883 under the Pendleton Act in order to eliminate the ill-effects of the spoils system, which saw that Presidents would commonly appoint friends and partners to crucial positions in the government despite vetting of qualifications.

The Classification Act of 1949 created a system of levels in the positions available in the federal government. These positions are sectioned out into levels of 1 through 13, increasing in compensation with the level. It seems as though promotion through these levels is contingent upon one’s ability to perform specific job duties, and this process of promotion is similar to the way in which private sector organizations function as well.