The milkmaid counted the eggs before she had the money — and the pail came off her head

A milkmaid carried a pail of milk on her head, walking to market to sell it. As she walked, she began to plan: with the money from the milk she would buy eggs, hatch chickens, sell the chickens, buy a dress, and then — wearing the fine dress — every young man at the dance would want to marry her. Lost in the daydream, she tossed her head. The pail fell. The milk spilled across the road.

The fable is one of Aesop's, found in Greek collections and later adapted by La Fontaine in his Fables Choisies (the Perrette story). It is the original source of the English idiom 'to count one's chickens before they are hatched.' The fable is unusual among Aesop's in that the mistake is not a vice — greed, vanity, cruelty — but a cognitive error: confusing projected returns with money already in hand.

The milkmaid made no bad decision about the milk itself. She priced it fairly, chose a market day, carried it properly. The failure was entirely in the step between 'I will sell this milk' and 'I will wear a dress to the dance.' She treated a future revenue stream as a current asset and built a series of contingent decisions on top of it. One small motion undid the entire chain.