The example I used was the 152 people who arrived off the coast of Newfoundland in 1986. I was involved in that, because I had just been the high commissioner in Sri Lanka and had just returned. They had asylum in Germany, but I think it's reasonable to assume that they had heard there were much better benefits in Canada.
Basically, they're people who travel through countries where they could have made claims. Their primary objective, presumably, is to reach safety. But in fact their real objective is to go to a place where they can get a lot of benefits. Safety is not their first concern. They will move on to find a country. Canada is probably the most generous country in terms of benefits, so they try to get to Canada, even if it's the hardest to reach geographically.