The U.S. Navy instituted a downsizing program, "Perform To Serve" (PTS) six years ago, an effort to get rid of people it doesn't need (not possessing needed skills) or want (disciplinary or physical fitness problems). Initially only first term sailors, seeking to reenlist, had to basically reapply for their jobs. Now, junior NCOs also have to do so, including those with 10-14 years of service. Last year, 90 percent of those who applied, kept their jobs. The other ten percent were either offered a job in another area, or told they could not reenlist.
Changing technology has caused shortages in some jobs, and surpluses in others. The PTS program allows sailors in overmanned jobs to take aptitude tests to see if they qualify for training in another job. Some sailors can't make the cut, and have to leave.
There are other programs for determining who has to leave. For example, it was recently made easier for officers and NCOs eligible for retirement (having served at least twenty years) to leave before their current contract was up (NCOs re-enlist for 4-6 years at a time, while officers have contracts do basically the same thing). In addition, the navy is letting some younger sailors get out a year or two before their current contract is up, if they are in job categories that are overmanned.
The navy currently has a strength of 332,000, and wants to get that down to 326,000 within the next two years. At the same time, the navy wants to keep scarce, hard-to-train and difficult-to-keep technical specialists. In particular, there are always shortages of nuclear power techs for submarines, and special operations troops (SEALs and their support people). And then there are the new recruits, most of whom are only in (deliberately) for one term (usually four years). These have to be replaced, along with those who stay in, but later decide to get out. There's less of this with a recession going on.
Another way to downsize effectively is to raise all sorts of standards, forcing out those who don't measure up. This includes going after, well, appearance. The navy has already cracked down on sailors and officers who are overweight. But now, all officers must submit a full length photo of themselves, for their personnel record (which is examined to determine who gets promoted). The picture is to be a three quarter view, with left shoulder forward, against a plan, flat, background. The photo must be 4x6 inches. The photo must be marked with the officers name and date of the picture. The suggested uniform is service khaki (basically tan colored pants and shirt) without the hat.
Four years ago, a long standing requirement for a full length photo was dropped. The official reason was that because the navy had cracked down on overweight officers, the photo was not necessary anymore. The unofficial reason was that the photo often penalized officers who, well, "didn't look right." This could be everything from being "too ethnic" to "ugly." No one would ever admit this officially, but it was often heard when officers spoke among themselves. But after a year or so of that, it was realized that officers who appear to look the part, are more likely to get promoted. So the photo requirement was reinstated. Or, in milspeak, "reemphasize the integral elements of military bearing and physical fitness to service professionalism." Note that many naval heroes of the past were noted for their unappealing appearance.