...Combined with insecure casual employment, the workers...felt under unsustainable pressure to meet performance targets or they will lose their jobs.

"It’s a hellscape," said one of the workers....

...[C]asual workers at Amazon’s Melbourne warehouse got a starting pay rate of [AUD]$25.36 an hour.... That compares with casual rates of between $30 and $37 an hour at nearby warehouses where workers have been able to negotiate collective agreements....

...Warehouse pickers are issued with handheld electronic scanners that direct them to different aisles of the warehouse to collect products....

...As soon as one item is scanned, a solid bar on the bottom of the screen immediately starts to count down, showing how much time they have to reach their next item, which could be anywhere in the 24,000-square-metre warehouse.

If an item is not scanned within the required time, the worker’s "pick rate" is marked down. 

Workers...thought Amazon used casual employment and demanding KPIs to push workers’ productivity to the limits.

...Amazon's spokeswoman said the company had a culture based on safety and a positive working environment. A spokeswoman for Adecco said it took the health and safety of its "associates" seriously, and that their welfare was its "number one priority".

...[W]hile workers at Amazon's factory had the right to bargain with Adecco, they may not be able to access Amazon....