I think it`s the Big Iron attraction, as the cousins put it. If you are on a CRJ or Biz jet in a pretty well paid job in the rest of the world, the buzz to get in the right hand seat of a 747-400 at even a reduced salary is palpable. CX can put pilots of very low experience into the right seat of an airliner. Most other airlines do, and have done in the past.
So whilst CX are losing guys with experience to other carriers, there will always be a line up for F/O jobs at almost any price. The company´s trick is to make sure that training costs remain above the line (i.e. pre tax) so that the staff turnover is containable the shareholders.
The only measure that the CX board uses for pilot employment is crew cost per revenue tonne kilometer. As long as that measure decreases every year, they are content. How FOP makes it happen is up to them, but you can see where the pressure comes from.