Would you ever give back someone's bet if they clearly mis-read the board?

Hypothetically, if you were absolutely certain an opponent mis-read the board, and put in a raise when they would have otherwise folded, would you ever give them back their last bet?

This is something that's come up in some of Bart Hanson's videos. Usually the person who made a mistake is a recreational player, and Bart has advocated for giving them back their bet, to engender goodwill, keep them in the game, etc.

Would the size of the bet or pot affect your decision? If so, how? Does it matter if the opponent is a recreational player or a reg?