the returns from an activity or undertaking do not warrant the time, money or effort required—calque of French ‘le jeu ne vaut pas la chandelle’—1603, in John Florio’s translation of Montaigne’s Essays
the benefits of an endeavour are enough to outweigh the effort of pursuing it—USA, 1959—refers to the labour-intensive process of squeezing fruit to produce fresh juice
USA, 1949—a person (originally and chiefly a girl or a woman) who is especially talkative—popularised from 1960 onwards by a proprietary name for a child’s talking doll manufactured by Mattel
dishonest or deceitful actions, while they may offer a short-term advantage, do not lead to long-term success or well-being—1710, as ‘cheating never thrives’
UK, 1883—to stay at a hotel, inn, etc., that provides a bed for the night and breakfast the following morning—to stay at an establishment known as a ‘bed and breakfast’
Australia, 1934—an inexhaustible supply of something, especially money—alludes to The Magic Pudding (1918), by Norman Lindsay, in which a pudding instantly renews itself as it is sliced or eaten into
USA, 1946—a feeling of regret experienced after making a purchase—also, in extended use: a feeling of regret experienced after voting for a particular person or programme
wealth gained in one generation of a family will be lost by the third generation—USA, 1874—refers to a hard-working man wearing a shirt with nothing over it