Looking at the medal table after the first week, Mexico, Austria, Finland and India, among many others, are still not on the board.
Austria actually hasn't won a summer olympic medal since 2008. I wonder why it doesn't do as well as the other rich european countries with a similar population.
I'm also always surprised at how poorly India does at the Olympics. It's obviously a poor country, but with its gigantic population, there must be a middle and upper class in the hundreds of millions. They also have the facilities from the Commonwealth games.