To say the robots never make mistakes is completely incorrect. Their bidding on occasion is atrocious but worst is their lead against a NT contract - they tend to lead a card from a 3 card suit ( usually any card ) I suppose it balances out because sometimes you are declarer other times your defensive partner - I have been playing bridge for a very long time and if one thing would make give up the game is the frustration of playing with robots e.g. in a daylong tournament.