This is obviously taken into consideration, but I wouldn't say that it is the key reason. A very important reason is the fact that local decision makers can occupy a position for several years, so there is no loss of knowledge. Canadian employees may hold the position for two, three or four years. Once they are replaced, there is a loss of knowledge from the outset. Regarding long-term productivity, local officers are more productive than Canadian officers who must, first, get settled in with their family and, second, take two or three months to become familiar with local customs after settling in a new area.
On March 10th, 2011. See this statement in context.