A foreign multinational with headquarters outside of Canada would have some tendency to try to move debt into Canada by getting the Canadian subsidiary to borrow money, perhaps to invest in shares abroad or something else, on which you will get very little in the way of dividends, but which will get you a deduction in Canada and reduce the Canadian tax base. When the money moves out of Canada, it goes to a tax haven, and ultimately it may move around and go back to the parent outside of Canada.
Again, it's a very complicated issue, and that's only a very simple and elementary description.