Canada will lose out to a team were the other team plays an all out trap and happen to run into a hockey goalie.
1998, Canada dominates the Czech but loses out to a hot Hasek who gave his team a chance in the shoot out.
2006, Canada gets stoned despite out playing the Swiss badly, and loses to a hot goalie, lost to Russia also when Canada runs into a hot goalie.
Or if Canada meets Sweden, the only other team I imagine that can defeat Team Canada, in a skill to skill game.