There was a dearth of CNC machines on the market back in 2011-2012 due to Apple buying so many (via Foxconn, https://appleinsider.com/articles/11/10/21/catcher_

There was a dearth of CNC machines on the market back in 2011-2012 due to Apple buying so many (via Foxconn, https://appleinsider.com/articles/11/10/21/catcher_hoping_to_reopen_chinese_macbook_unibody_case_plant_in_november https://appleinsider.com/articles/11/10/21/catcher_hoping_to... ). But they were shared for iPhone production etc. This is the source for the 10 000 machines number. I however recall that they claimed in a keynote it took 10 hours to machine a single unibody MacBook, which would make the capacity for a single machine about 700 cases a year.