Lasting for more than a year as an Amazon warehouse employee is notoriously difficult. Some workers walk up to 15 miles a shift, while others pack hundreds of boxes an hour—moving in repetitive, forceful positions that lead to frequent—and sometimes lifelong— injuries to shoulders, necks, backs, wrists and knees. Worse yet, Amazon is known to track and fire workers for lack of “efficiency.”

Indeed, according to a report released Friday by the National Employment Law Project, which analyzes census data in California, Amazon warehouses have uniquely high rates of turnover for the warehouse industry.

Between 2011—the year the first fulfillment center opened in California— and 2017, the turnover rate in five counties with Amazon warehouses leaped from 38 percent to 100 percent, according to the report. In other words, more warehouse workers departed from their jobs each year in counties with an Amazon presence than the total number of warehouse jobs.

“What emerges is a troubling picture of Amazon’s business model—one in which the company views its workers as disposable and designs its operations to foster high turnover,” the report’s authors wrote. “The particularly high rate [of turnover for Amazon] workers as compared to the rate for similar workers suggests that Amazon’s presence has had a unique impact.”

By comparison, overall turnover rates for warehouse workers in California are 20 percent lower than they are in counties without Amazon warehouses, at 83 percent.

“Workers who can’t keep up with extreme productivity goals are fired or encouraged to quit. Many workers have to leave their jobs because of injuries,” they continued. “Amazon’s inhumane work pace and repetitive work tasks require a level of physical exertion and strain that takes a high toll on workers’ physical health over time, which is why the company needs to constantly replenish its workforce with fresh bodies.”

"We’re constantly exploring, piloting, and fine-tuning technology designed to reduce risk and prevent injury," Amazon spokesperson Rachael Lighty said. "The use of robotics, automation and technology in our fulfillment centers is enhancing our workplace, making jobs safer, easier and more efficient. In addition, we recently rolled out a new wellness program designed to prompt and encourage employees to pause each hour to stretch, meditate and or take a mindful moment at their ergonomically-designed work stations. Last year, we provided more than one million hours of safety training to employees across the U.S. and committed to investing more than $61 million in safety improvement projects."

For example, in Riverside County—a sprawling Amazon logistics hub that serves Southern California—which is home to six Amazon fulfillment centers, warehouse workers left their jobs 28,685 times in 2017. That number is exceedingly high considering that Riverside County only had 26,928 warehouse jobs that year.

Meanwhile, Amazon repeatedly advertises its commitment to treating its warehouse employees with dignity—inviting seemingly anyone to tour specific warehouse facility and touting its commitment to paying all of its full-time workers at least $15 an hour with benefits.

The darker side of this is that Amazon seems to actually prefer its high turnover rates—offering warehouse workers between $2,000 and $5,000 to walk out the door after a few years of service, with the caveat that they can never work for the e-commerce giant again.

“Most companies try to reduce their turnover, but when we started to look into this, we were like that’s not what Amazon is trying to do,” said Irene Tung, one of the report’s authors told Motherboard. “They’ve made a decision to have an extreme pace of work and they need a stream of new workers for a short period of time. Amazon has figured out that that’s how they maintain ultra high productivity metrics.”

The report arrives during a surge of coordinated organizing in Amazon warehouses across the country—in particular about the high rate workplace injuries. In recent months, former and current Amazon warehouse workers in Chicago, New York City, Sacramento, Shakopee, Minnesota, and California’s Inland Empire have protested working conditions. Most recently, on Thursday, former Amazon warehouse workers in California’s Inland Empire—highlighted in the turnover report— disrupted a conference, where Amazon’s vice president of workplace safety spoke about the role of technology in safety.

"Amazon is invested in the long-term success of our employees and is proud to provide a safe, quality work environment," Lighty said. "As we continue to grow, we also ensure long-term career development opportunities for our employees and promoted more than 19,000 Operations associates last year alone. We provide all associates with career development opportunities through training, Career Skills courses, and our innovative Career Choice program, which prepays 95 percent of tuition for associates."