[MIJB#19]

The problem with this kind of data (and this is my presumption on it) is that they will not take into account the other variables at work. You can't blindly go by goalkeeper A stopped 20% and goalkeeper B stopped 24% during their careers. Are penalty kicks during a match the same as penalty shootouts? Was there prior research about whether flipping goalkeepers will improve or decrease the incoming "cold" goalkeeper's chances to stop kicks?

if Goalkeeper A stopped 3 of 15 penalties and Goalkeeper B stopped 6 of 25 penalties, that obviously isn't enough data. And even if we it's 5 times these figures, there are so many other variables. Which teams and players did they face? Which team took the first kick? Were they playing in front of a home crowd? Was this a televised game? Did he break up with his girlfriend or become a daddy recently? Did it rain? Were the floodlights on? Did he play "I know you know so you know I know" mind games with the kick takers? Did lightning strike in a bottle? Was he up for renewal of a contract? Did his team lead or trail for a long time during the game, or was it a 0-0 snoozer? Does he think that the color of the shirt worn makes a difference?