A complete mess / a can of worms
A lista de exigências virou um balaio de gato no fim do projeto.
The list of requirements turned into a complete mess by the end of the project.
A balaio is a wide basket woven from thick straw or wicker, once common on farms and in homes. The image behind balaio de gato is plain: imagine several cats shut inside one basket — a squirming, snarling tangle.
Source: Aulete.
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