Don't forget the last surprise in the round of 16 was how Morocco beat Spain on penalties, Spain controlled more than 60% of the ball positions but couldn't score a single goal and what's even more strange was their 3 penalty takers missed including a penalty from the captain of their national team's bad record and just like Japan which doesn't have a sharp penalty shooter.
Penalties are a bit based on luck as much as scoring, if you are not doing some panenke or whatever it is called, then you are going to shoot the ball, these are million dollar valued players and can shoot the ball we all know that, but sometimes you just fail to put it where you want to, between the stress and the tiredness and indecisiveness, there are many factors to put in.
Many people joked about Ronaldo and how he scored plenty from penalties, but I hope all those people realized why it is important to be consistent at scoring from penalties and how every team needs at least one guy like that. Spain lacked a proper striker, and that caused their elimination.