Probably the same factors that would affect students, attraction as well as retention. The attraction is would they even consider manufacturing? If it is viewed as dirty assembly line work of the past, that's not exciting to them, and they'll run to other areas and they'll go to other engineering fields where they see much more advanced technology at work.
On the retention side, once they get to know the field a little bit, they start to hear of the issues you're discussing here: I got into it, but will there be a job for me, or are all the jobs going to be out of the country? That scares the daylights out of students. They may want to go and work internationally in time, but that probably was not their objective when they got into a program, that they were signing, basically, their immigration papers and they would have to leave. If they don't see a future in the field in Canada, they're not going to go into it and you get into that spiral. You can't get into the service sector because no one wants to get into it, but with no one there, you can't beef up the sector.