For many of the reasons some members have already stated.
I'm Canadian, my wife is not. We've been living in a Southern Mediterranean country for the last decade. It was really fun to travel and discover Southern Europe and Northern Africa. We had the best of times traveling Africa north and south, east and west. But it started to be less fun when our children started to grow (the oldest is 9, the youngest almost 3). Schools are awful, the French system of education is lagging, centuries behind, bureaucracy is killing us, houses are as expensive as what we see in some Quebec metropolitan areas, for example. Everything is getting expensive, way more than in Canada sometimes.
It's all those things like that - that seem little at first - that have influenced our decision to go live in Canada.