This could have happened due to pressure.
Explanation:
Human muscle memory is reliable in normal conditions.
LEBron James had one of the best hands in the game and would never miss a foul shot but the pressure of the game would have been so great that he missed.
Psychological duress and the pressure of expectations make people double check and doubt their own muscle memory which may sometimes falter and make them commit mistakes they would not otherwise do.
This is what happens here.
