During today's Street Chess there was a game where the generosity of one player was rewarded, but maybe it shouldn't have been. In the game given below, after Black had played 10. ... Nd4 White instinctively touched the knight on f3 to capture it. But before White could complete the move, he paused, and then Black told him he didn't have to move it. So White put the knight down, and after some thought played 11.Bb5+ instead.
It of course turns out that White's best move would have been to take the knight on d4, offering a queen sacrifice. With best play the game is almost equal (Black has to give the queen back), but there is a mate for White if Black moves his king to e7.
The move that White chose did not lose the queen, but it did eventually lose the game, as Black won enough material to easily gain an advantage.
Street Chess 31 October 2020