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In 2007, Bar-Eli, Azar, Ritov, Keidar-Levin and Schein published an analysis of 286 elite penalty kicks in the Journal of Economic Psychology. The kicks were taken in the Champions League, the Spanish Copa del Rey, the World Cup and the Bundesliga. The numbers:
1. Goalkeepers dive to one side 94% of the time. They stay in the middle only 6% of the time. 2. The shots go left 32% of the time, right 39%, and straight down the middle 29%. 3. The best save rate belonged to keepers who did not move: they stopped 33% of the shots that came at the middle. Diving left saved 14%. Diving right, 13%.
It is called action bias. When the same keepers were surveyed, almost all of them said that a goal conceded while standing still hurt more than a goal conceded while diving and missing. It is easier to justify «I tried» than «I did nothing»: in front of the net, in a meeting room, in your inbox.