The Army offers a handful of major incentives to keep soldiers on board, the main one being retention bonuses. About 45% of soldiers who extend their contracts get those bonuses, the average of which was $14,000 this year. In rare cases, those bonuses can be up to $81,000, but that money is usually reserved for highly technical jobs covering only a relatively small number of soldiers. Troops coming up on the end of their contract sometimes also have room to negotiate their duty station or job.

"Some people want to just stay where they're at," Whitney said. "We offer them the opportunity to stabilize there for up to 30 months. So now, for the next 30 months, if you reenlist, you will be guaranteed to stay at your duty station, so that you can stabilize your family or if you're going to school, whatever the situation may be. And this is the largest incentive that we see people taking is a different duty station or a different [job]."

The top reason soldiers want to continue their Army career is retirement pay, which soldiers typically can earn after 20 years of service, according to a 2021 service study. Generally, a soldier is most likely to leave after their first contract, which is usually four years and when a soldier is typically on the cusp of being promoted into a leadership role as a non-commissioned officer. After that, a soldier becomes less and less likely to leave the service as they get closer to that 20-year mark. Soldiers are also often motivated to continue their career for benefits, such as health care.

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Some troops leave simply because Army life wasn't for them or they had a poor experience, but one major concern among service leadership is the competition with the civilian workforce, especially for soldiers in technical jobs. The Army has often invested heavily in training those troops, but the skill sets they've developed are highly desirable to outside employers. But even in jobs, such as combat arms, for which the training pipeline and barrier to entry is less complicated, job opportunities can still lure soldiers.

"There are a lot of other government agencies that are really targeting those folks to go work in law enforcement, fire departments or the FBI, for example," Whitney said. "We're competing against other governmental agencies, because we have the people that have the talent and the skills and they have a proven record of being able to perform at a high level, and so those people are very sought after."

The biggest reason soldiers leave, according to the 2021 study, is the effect service has on their families and their lack of predictability in Army life. Service leaders have made some adjustments, such as a quality-of-life improvements for families, including extended leave in the wake of miscarriages and new rules that aim to make pumping breast milk easier while on duty.

Yet the service continues to struggle with issues such as rampant mold infestations in its barracks and family housing. The Army is also coming off two decades of the post-9/11 wars, and while deployments are less frequent, units are still constantly rotating into Europe, Africa and the Pacific, in addition to long-term training exercises at home such as at the National Training Center at Fort Irwin, California.

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With what is effectively a peacetime Army, it is unclear how that will impact retention. Combat deployments are sometimes seen as a way to build camaraderie in units. Some recruits, especially in combat arms roles, join specifically for the chance to fight. On the flip side, combat deployments cause a lot of stress on families and can quickly burn some soldiers out.

"It probably averages out," Whitney said about whether a lack of a war makes retention easier or more difficult.

While the Army has been successful with retention, the active component of the Army is expected to be short as many as 15,000 new recruits this year due to a mixture of issues, such as the majority of young Americans being too overweight to serve or unable to pass the service's academic entrance exam.

High retention paired with trouble recruiting for years at a time could create a top-heavy Army, with too many soldiers in leadership roles and not enough new privates to fill in the ranks, although service leaders have yet to sound the alarm about such a possibility.

While the active-duty component is having no issue retaining its troops, the National Guard is bleeding out soldiers on multiple fronts -- with soldiers swiftly heading for the exit while an additional 40,000 are set to be discharged for refusing to be inoculated against COVID-19. The Guard could see itself short tens of thousands of soldiers by 2025.

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This year, the Guard will miss its retention goal by about 4,800 soldiers, or about 14%. That grim number might be one of the first signs that the extensive use of the Guard during the pandemic, with units on near constant domestic missions running from protecting the Capitol after the insurrection to missions far outside its typical Rolodex, including substitute teaching and bus driving, is taking a toll.