Their crewing system operates on the basis of mass of young people on short term employment. Their re-enlistment rate after five years is quite low compared to most other NATO nations. As a result, they trained them quickly in one specific job to get the most out of their service.
To give you an example: We operated our PB's (ex-minesweepers) in the old days with two classes of engineers: One electrician and seven MarEng Tech. A similar American minesweeper had seven different categories of engineers for a total of 16, because the operators could not be the maintainers, and the people doing diesels could not be the ones doing generators or small engine repairs, etc. etc.
That's why you have over 5,500 people to operate aircraft carriers, most of whom are under the age of 24, when most other nations that have them do so with less than half that number. Another example: we have all the electronics work done by our Weapons tech in Canada. The US would have a HF radio tech, a UHF radio tech, a Aegis radar tech, a Navigation radar tech, etc. While each one of those technician knows the sole system it is there to fix like the back of their hand, none of these techs would be able to step into the next one's shoes, so redundancy is made by having more techs of all types than needed. A Canadian NWT would be a little slower at fixing things, but can do them all.