too many irons in the fire

Example: “Between the startup, the band and night school, he has too many irons in the fire.”

Origin: From the forge, and the failure it describes is specific rather than general. A smith heats iron in the fire and works it during the narrow window in which it is hot enough to shape, so several pieces can reasonably be in the coals at once — but only as many as can be reached before any of them overheat. Iron left too long is not merely too hot to handle: it burns, its structure is spoiled beyond repair, and the piece is scrap. The idiom therefore does not simply mean being busy. It names a particular kind of overcommitment in which the cost is not exhaustion but ruined work, incurred precisely while attention is elsewhere. The phrase is attested in English from the 1500s.