Not an expert on the topic, but two factors come to mind:
-The cost of a medical degree in Canada is relatively cheap, so med students not intending to practice there are incentivized to study there and leave the country shortly after graduating. This is a double whammy because for every doctor who leaves, a doctor who would have stayed could have been trained in their stead.
-Doctors can easily move across the southern border to earn much more than they would in Canada.
Do Canadians not have enough doctors to go around?
Not an expert on the topic, but two factors come to mind:
-The cost of a medical degree in Canada is relatively cheap, so med students not intending to practice there are incentivized to study there and leave the country shortly after graduating. This is a double whammy because for every doctor who leaves, a doctor who would have stayed could have been trained in their stead.
-Doctors can easily move across the southern border to earn much more than they would in Canada.