It's wrong to betray your children's trust.
Jim promised to buy his son a new game if he kept his grades up and the report card shows good grades.
Jim wants to save money for more essential items.
Jim finds a coupon code for a discount on the game.
Jim does not end up buying his son the game despite his grades.
Jim's son is happy and believes he will be rewarded for his good deeds.
Jim's son now has trouble believing he will keep his word.