In my experience the problem is on the delivery side within Canada, as opposed to mail managing to make it out of Canada to the right country
. Canada Post regularly delivers mail to the wrong address. I really can't understand it, walking and reading are pretty much the only skills required to deliver mail. For months I was getting a distant neighbour's magazine subscription which was correctly addressed to them on another street with a completely different house number. I recently had a valuable badge delivered to me by another distant neighbour, it took four weeks to get to me from within Canada and it too was correctly addressed. I could go on, I've been at the same address for 15 years and it has been an ongoing problem.
Now Canada Post's big idea is "flexible delivery", which means no delivery at all - you can choose to pick up your mail at the nearest post office. I think I actually like this idea because it removes the weakest link! Maybe they will expand this idea so we can pick up our mail at the nearest international airport and really fix the problem!
I hope I haven't offended any Canadian Posties, I reckon I get 99% of my mail first go around but some of the 1% has been painful.
Cheers, Ian.